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linux/fs/xfs/xfs_inode.c

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/*
* Copyright (c) 2000-2006 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/log2.h>
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_buf_item.h"
#include "xfs_inode_item.h"
#include "xfs_btree.h"
#include "xfs_btree_trace.h"
#include "xfs_alloc.h"
#include "xfs_ialloc.h"
#include "xfs_bmap.h"
#include "xfs_error.h"
#include "xfs_utils.h"
#include "xfs_quota.h"
#include "xfs_filestream.h"
#include "xfs_vnodeops.h"
#include "xfs_trace.h"
kmem_zone_t *xfs_ifork_zone;
kmem_zone_t *xfs_inode_zone;
/*
* Used in xfs_itruncate(). This is the maximum number of extents
* freed from a file in a single transaction.
*/
#define XFS_ITRUNC_MAX_EXTENTS 2
STATIC int xfs_iflush_int(xfs_inode_t *, xfs_buf_t *);
STATIC int xfs_iformat_local(xfs_inode_t *, xfs_dinode_t *, int, int);
STATIC int xfs_iformat_extents(xfs_inode_t *, xfs_dinode_t *, int);
STATIC int xfs_iformat_btree(xfs_inode_t *, xfs_dinode_t *, int);
#ifdef DEBUG
/*
* Make sure that the extents in the given memory buffer
* are valid.
*/
STATIC void
xfs_validate_extents(
xfs_ifork_t *ifp,
int nrecs,
xfs_exntfmt_t fmt)
{
xfs_bmbt_irec_t irec;
xfs_bmbt_rec_host_t rec;
int i;
for (i = 0; i < nrecs; i++) {
xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
rec.l0 = get_unaligned(&ep->l0);
rec.l1 = get_unaligned(&ep->l1);
xfs_bmbt_get_all(&rec, &irec);
if (fmt == XFS_EXTFMT_NOSTATE)
ASSERT(irec.br_state == XFS_EXT_NORM);
}
}
#else /* DEBUG */
#define xfs_validate_extents(ifp, nrecs, fmt)
#endif /* DEBUG */
/*
* Check that none of the inode's in the buffer have a next
* unlinked field of 0.
*/
#if defined(DEBUG)
void
xfs_inobp_check(
xfs_mount_t *mp,
xfs_buf_t *bp)
{
int i;
int j;
xfs_dinode_t *dip;
j = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
for (i = 0; i < j; i++) {
dip = (xfs_dinode_t *)xfs_buf_offset(bp,
i * mp->m_sb.sb_inodesize);
if (!dip->di_next_unlinked) {
xfs_alert(mp,
"Detected bogus zero next_unlinked field in incore inode buffer 0x%p.",
bp);
ASSERT(dip->di_next_unlinked);
}
}
}
#endif
/*
* Find the buffer associated with the given inode map
* We do basic validation checks on the buffer once it has been
* retrieved from disk.
*/
STATIC int
xfs_imap_to_bp(
xfs_mount_t *mp,
xfs_trans_t *tp,
struct xfs_imap *imap,
xfs_buf_t **bpp,
uint buf_flags,
uint iget_flags)
{
int error;
int i;
int ni;
xfs_buf_t *bp;
error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap->im_blkno,
(int)imap->im_len, buf_flags, &bp);
if (error) {
if (error != EAGAIN) {
xfs_warn(mp,
"%s: xfs_trans_read_buf() returned error %d.",
__func__, error);
} else {
ASSERT(buf_flags & XBF_TRYLOCK);
}
return error;
}
/*
* Validate the magic number and version of every inode in the buffer
* (if DEBUG kernel) or the first inode in the buffer, otherwise.
*/
#ifdef DEBUG
ni = BBTOB(imap->im_len) >> mp->m_sb.sb_inodelog;
#else /* usual case */
ni = 1;
#endif
for (i = 0; i < ni; i++) {
int di_ok;
xfs_dinode_t *dip;
dip = (xfs_dinode_t *)xfs_buf_offset(bp,
(i << mp->m_sb.sb_inodelog));
di_ok = be16_to_cpu(dip->di_magic) == XFS_DINODE_MAGIC &&
XFS_DINODE_GOOD_VERSION(dip->di_version);
if (unlikely(XFS_TEST_ERROR(!di_ok, mp,
XFS_ERRTAG_ITOBP_INOTOBP,
XFS_RANDOM_ITOBP_INOTOBP))) {
if (iget_flags & XFS_IGET_UNTRUSTED) {
xfs_trans_brelse(tp, bp);
return XFS_ERROR(EINVAL);
}
XFS_CORRUPTION_ERROR("xfs_imap_to_bp",
XFS_ERRLEVEL_HIGH, mp, dip);
#ifdef DEBUG
xfs_emerg(mp,
"bad inode magic/vsn daddr %lld #%d (magic=%x)",
(unsigned long long)imap->im_blkno, i,
be16_to_cpu(dip->di_magic));
ASSERT(0);
#endif
xfs_trans_brelse(tp, bp);
return XFS_ERROR(EFSCORRUPTED);
}
}
xfs_inobp_check(mp, bp);
/*
* Mark the buffer as an inode buffer now that it looks good
*/
XFS_BUF_SET_VTYPE(bp, B_FS_INO);
*bpp = bp;
return 0;
}
/*
* This routine is called to map an inode number within a file
* system to the buffer containing the on-disk version of the
* inode. It returns a pointer to the buffer containing the
* on-disk inode in the bpp parameter, and in the dip parameter
* it returns a pointer to the on-disk inode within that buffer.
*
* If a non-zero error is returned, then the contents of bpp and
* dipp are undefined.
*
* Use xfs_imap() to determine the size and location of the
* buffer to read from disk.
*/
int
xfs_inotobp(
xfs_mount_t *mp,
xfs_trans_t *tp,
xfs_ino_t ino,
xfs_dinode_t **dipp,
xfs_buf_t **bpp,
int *offset,
uint imap_flags)
{
struct xfs_imap imap;
xfs_buf_t *bp;
int error;
imap.im_blkno = 0;
error = xfs_imap(mp, tp, ino, &imap, imap_flags);
if (error)
return error;
error = xfs_imap_to_bp(mp, tp, &imap, &bp, XBF_LOCK, imap_flags);
if (error)
return error;
*dipp = (xfs_dinode_t *)xfs_buf_offset(bp, imap.im_boffset);
*bpp = bp;
*offset = imap.im_boffset;
return 0;
}
/*
* This routine is called to map an inode to the buffer containing
* the on-disk version of the inode. It returns a pointer to the
* buffer containing the on-disk inode in the bpp parameter, and in
* the dip parameter it returns a pointer to the on-disk inode within
* that buffer.
*
* If a non-zero error is returned, then the contents of bpp and
* dipp are undefined.
*
* The inode is expected to already been mapped to its buffer and read
* in once, thus we can use the mapping information stored in the inode
* rather than calling xfs_imap(). This allows us to avoid the overhead
* of looking at the inode btree for small block file systems
* (see xfs_imap()).
*/
int
xfs_itobp(
xfs_mount_t *mp,
xfs_trans_t *tp,
xfs_inode_t *ip,
xfs_dinode_t **dipp,
xfs_buf_t **bpp,
uint buf_flags)
{
xfs_buf_t *bp;
int error;
ASSERT(ip->i_imap.im_blkno != 0);
error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp, buf_flags, 0);
if (error)
return error;
if (!bp) {
ASSERT(buf_flags & XBF_TRYLOCK);
ASSERT(tp == NULL);
*bpp = NULL;
return EAGAIN;
}
*dipp = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
*bpp = bp;
return 0;
}
/*
* Move inode type and inode format specific information from the
* on-disk inode to the in-core inode. For fifos, devs, and sockets
* this means set if_rdev to the proper value. For files, directories,
* and symlinks this means to bring in the in-line data or extent
* pointers. For a file in B-tree format, only the root is immediately
* brought in-core. The rest will be in-lined in if_extents when it
* is first referenced (see xfs_iread_extents()).
*/
STATIC int
xfs_iformat(
xfs_inode_t *ip,
xfs_dinode_t *dip)
{
xfs_attr_shortform_t *atp;
int size;
int error;
xfs_fsize_t di_size;
ip->i_df.if_ext_max =
XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
error = 0;
if (unlikely(be32_to_cpu(dip->di_nextents) +
be16_to_cpu(dip->di_anextents) >
be64_to_cpu(dip->di_nblocks))) {
xfs_warn(ip->i_mount,
"corrupt dinode %Lu, extent total = %d, nblocks = %Lu.",
(unsigned long long)ip->i_ino,
(int)(be32_to_cpu(dip->di_nextents) +
be16_to_cpu(dip->di_anextents)),
(unsigned long long)
be64_to_cpu(dip->di_nblocks));
XFS_CORRUPTION_ERROR("xfs_iformat(1)", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
if (unlikely(dip->di_forkoff > ip->i_mount->m_sb.sb_inodesize)) {
xfs_warn(ip->i_mount, "corrupt dinode %Lu, forkoff = 0x%x.",
(unsigned long long)ip->i_ino,
dip->di_forkoff);
XFS_CORRUPTION_ERROR("xfs_iformat(2)", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
if (unlikely((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) &&
!ip->i_mount->m_rtdev_targp)) {
xfs_warn(ip->i_mount,
"corrupt dinode %Lu, has realtime flag set.",
ip->i_ino);
XFS_CORRUPTION_ERROR("xfs_iformat(realtime)",
XFS_ERRLEVEL_LOW, ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
switch (ip->i_d.di_mode & S_IFMT) {
case S_IFIFO:
case S_IFCHR:
case S_IFBLK:
case S_IFSOCK:
if (unlikely(dip->di_format != XFS_DINODE_FMT_DEV)) {
XFS_CORRUPTION_ERROR("xfs_iformat(3)", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
ip->i_d.di_size = 0;
ip->i_size = 0;
ip->i_df.if_u2.if_rdev = xfs_dinode_get_rdev(dip);
break;
case S_IFREG:
case S_IFLNK:
case S_IFDIR:
switch (dip->di_format) {
case XFS_DINODE_FMT_LOCAL:
/*
* no local regular files yet
*/
if (unlikely((be16_to_cpu(dip->di_mode) & S_IFMT) == S_IFREG)) {
xfs_warn(ip->i_mount,
"corrupt inode %Lu (local format for regular file).",
(unsigned long long) ip->i_ino);
XFS_CORRUPTION_ERROR("xfs_iformat(4)",
XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
di_size = be64_to_cpu(dip->di_size);
if (unlikely(di_size > XFS_DFORK_DSIZE(dip, ip->i_mount))) {
xfs_warn(ip->i_mount,
"corrupt inode %Lu (bad size %Ld for local inode).",
(unsigned long long) ip->i_ino,
(long long) di_size);
XFS_CORRUPTION_ERROR("xfs_iformat(5)",
XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
size = (int)di_size;
error = xfs_iformat_local(ip, dip, XFS_DATA_FORK, size);
break;
case XFS_DINODE_FMT_EXTENTS:
error = xfs_iformat_extents(ip, dip, XFS_DATA_FORK);
break;
case XFS_DINODE_FMT_BTREE:
error = xfs_iformat_btree(ip, dip, XFS_DATA_FORK);
break;
default:
XFS_ERROR_REPORT("xfs_iformat(6)", XFS_ERRLEVEL_LOW,
ip->i_mount);
return XFS_ERROR(EFSCORRUPTED);
}
break;
default:
XFS_ERROR_REPORT("xfs_iformat(7)", XFS_ERRLEVEL_LOW, ip->i_mount);
return XFS_ERROR(EFSCORRUPTED);
}
if (error) {
return error;
}
if (!XFS_DFORK_Q(dip))
return 0;
ASSERT(ip->i_afp == NULL);
ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_SLEEP | KM_NOFS);
ip->i_afp->if_ext_max =
XFS_IFORK_ASIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
switch (dip->di_aformat) {
case XFS_DINODE_FMT_LOCAL:
atp = (xfs_attr_shortform_t *)XFS_DFORK_APTR(dip);
size = be16_to_cpu(atp->hdr.totsize);
if (unlikely(size < sizeof(struct xfs_attr_sf_hdr))) {
xfs_warn(ip->i_mount,
"corrupt inode %Lu (bad attr fork size %Ld).",
(unsigned long long) ip->i_ino,
(long long) size);
XFS_CORRUPTION_ERROR("xfs_iformat(8)",
XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK, size);
break;
case XFS_DINODE_FMT_EXTENTS:
error = xfs_iformat_extents(ip, dip, XFS_ATTR_FORK);
break;
case XFS_DINODE_FMT_BTREE:
error = xfs_iformat_btree(ip, dip, XFS_ATTR_FORK);
break;
default:
error = XFS_ERROR(EFSCORRUPTED);
break;
}
if (error) {
kmem_zone_free(xfs_ifork_zone, ip->i_afp);
ip->i_afp = NULL;
xfs_idestroy_fork(ip, XFS_DATA_FORK);
}
return error;
}
/*
* The file is in-lined in the on-disk inode.
* If it fits into if_inline_data, then copy
* it there, otherwise allocate a buffer for it
* and copy the data there. Either way, set
* if_data to point at the data.
* If we allocate a buffer for the data, make
* sure that its size is a multiple of 4 and
* record the real size in i_real_bytes.
*/
STATIC int
xfs_iformat_local(
xfs_inode_t *ip,
xfs_dinode_t *dip,
int whichfork,
int size)
{
xfs_ifork_t *ifp;
int real_size;
/*
* If the size is unreasonable, then something
* is wrong and we just bail out rather than crash in
* kmem_alloc() or memcpy() below.
*/
if (unlikely(size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) {
xfs_warn(ip->i_mount,
"corrupt inode %Lu (bad size %d for local fork, size = %d).",
(unsigned long long) ip->i_ino, size,
XFS_DFORK_SIZE(dip, ip->i_mount, whichfork));
XFS_CORRUPTION_ERROR("xfs_iformat_local", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
ifp = XFS_IFORK_PTR(ip, whichfork);
real_size = 0;
if (size == 0)
ifp->if_u1.if_data = NULL;
else if (size <= sizeof(ifp->if_u2.if_inline_data))
ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
else {
real_size = roundup(size, 4);
ifp->if_u1.if_data = kmem_alloc(real_size, KM_SLEEP | KM_NOFS);
}
ifp->if_bytes = size;
ifp->if_real_bytes = real_size;
if (size)
memcpy(ifp->if_u1.if_data, XFS_DFORK_PTR(dip, whichfork), size);
ifp->if_flags &= ~XFS_IFEXTENTS;
ifp->if_flags |= XFS_IFINLINE;
return 0;
}
/*
* The file consists of a set of extents all
* of which fit into the on-disk inode.
* If there are few enough extents to fit into
* the if_inline_ext, then copy them there.
* Otherwise allocate a buffer for them and copy
* them into it. Either way, set if_extents
* to point at the extents.
*/
STATIC int
xfs_iformat_extents(
xfs_inode_t *ip,
xfs_dinode_t *dip,
int whichfork)
{
xfs_bmbt_rec_t *dp;
xfs_ifork_t *ifp;
int nex;
int size;
int i;
ifp = XFS_IFORK_PTR(ip, whichfork);
nex = XFS_DFORK_NEXTENTS(dip, whichfork);
size = nex * (uint)sizeof(xfs_bmbt_rec_t);
/*
* If the number of extents is unreasonable, then something
* is wrong and we just bail out rather than crash in
* kmem_alloc() or memcpy() below.
*/
if (unlikely(size < 0 || size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) {
xfs_warn(ip->i_mount, "corrupt inode %Lu ((a)extents = %d).",
(unsigned long long) ip->i_ino, nex);
XFS_CORRUPTION_ERROR("xfs_iformat_extents(1)", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
ifp->if_real_bytes = 0;
if (nex == 0)
ifp->if_u1.if_extents = NULL;
else if (nex <= XFS_INLINE_EXTS)
ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
else
xfs_iext_add(ifp, 0, nex);
ifp->if_bytes = size;
if (size) {
dp = (xfs_bmbt_rec_t *) XFS_DFORK_PTR(dip, whichfork);
xfs_validate_extents(ifp, nex, XFS_EXTFMT_INODE(ip));
for (i = 0; i < nex; i++, dp++) {
xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
ep->l0 = get_unaligned_be64(&dp->l0);
ep->l1 = get_unaligned_be64(&dp->l1);
}
XFS_BMAP_TRACE_EXLIST(ip, nex, whichfork);
if (whichfork != XFS_DATA_FORK ||
XFS_EXTFMT_INODE(ip) == XFS_EXTFMT_NOSTATE)
if (unlikely(xfs_check_nostate_extents(
ifp, 0, nex))) {
XFS_ERROR_REPORT("xfs_iformat_extents(2)",
XFS_ERRLEVEL_LOW,
ip->i_mount);
return XFS_ERROR(EFSCORRUPTED);
}
}
ifp->if_flags |= XFS_IFEXTENTS;
return 0;
}
/*
* The file has too many extents to fit into
* the inode, so they are in B-tree format.
* Allocate a buffer for the root of the B-tree
* and copy the root into it. The i_extents
* field will remain NULL until all of the
* extents are read in (when they are needed).
*/
STATIC int
xfs_iformat_btree(
xfs_inode_t *ip,
xfs_dinode_t *dip,
int whichfork)
{
xfs_bmdr_block_t *dfp;
xfs_ifork_t *ifp;
/* REFERENCED */
int nrecs;
int size;
ifp = XFS_IFORK_PTR(ip, whichfork);
dfp = (xfs_bmdr_block_t *)XFS_DFORK_PTR(dip, whichfork);
size = XFS_BMAP_BROOT_SPACE(dfp);
nrecs = be16_to_cpu(dfp->bb_numrecs);
/*
* blow out if -- fork has less extents than can fit in
* fork (fork shouldn't be a btree format), root btree
* block has more records than can fit into the fork,
* or the number of extents is greater than the number of
* blocks.
*/
if (unlikely(XFS_IFORK_NEXTENTS(ip, whichfork) <= ifp->if_ext_max
|| XFS_BMDR_SPACE_CALC(nrecs) >
XFS_DFORK_SIZE(dip, ip->i_mount, whichfork)
|| XFS_IFORK_NEXTENTS(ip, whichfork) > ip->i_d.di_nblocks)) {
xfs_warn(ip->i_mount, "corrupt inode %Lu (btree).",
(unsigned long long) ip->i_ino);
XFS_CORRUPTION_ERROR("xfs_iformat_btree", XFS_ERRLEVEL_LOW,
ip->i_mount, dip);
return XFS_ERROR(EFSCORRUPTED);
}
ifp->if_broot_bytes = size;
ifp->if_broot = kmem_alloc(size, KM_SLEEP | KM_NOFS);
ASSERT(ifp->if_broot != NULL);
/*
* Copy and convert from the on-disk structure
* to the in-memory structure.
*/
xfs_bmdr_to_bmbt(ip->i_mount, dfp,
XFS_DFORK_SIZE(dip, ip->i_mount, whichfork),
ifp->if_broot, size);
ifp->if_flags &= ~XFS_IFEXTENTS;
ifp->if_flags |= XFS_IFBROOT;
return 0;
}
STATIC void
xfs_dinode_from_disk(
xfs_icdinode_t *to,
xfs_dinode_t *from)
{
to->di_magic = be16_to_cpu(from->di_magic);
to->di_mode = be16_to_cpu(from->di_mode);
to->di_version = from ->di_version;
to->di_format = from->di_format;
to->di_onlink = be16_to_cpu(from->di_onlink);
to->di_uid = be32_to_cpu(from->di_uid);
to->di_gid = be32_to_cpu(from->di_gid);
to->di_nlink = be32_to_cpu(from->di_nlink);
to->di_projid_lo = be16_to_cpu(from->di_projid_lo);
to->di_projid_hi = be16_to_cpu(from->di_projid_hi);
memcpy(to->di_pad, from->di_pad, sizeof(to->di_pad));
to->di_flushiter = be16_to_cpu(from->di_flushiter);
to->di_atime.t_sec = be32_to_cpu(from->di_atime.t_sec);
to->di_atime.t_nsec = be32_to_cpu(from->di_atime.t_nsec);
to->di_mtime.t_sec = be32_to_cpu(from->di_mtime.t_sec);
to->di_mtime.t_nsec = be32_to_cpu(from->di_mtime.t_nsec);
to->di_ctime.t_sec = be32_to_cpu(from->di_ctime.t_sec);
to->di_ctime.t_nsec = be32_to_cpu(from->di_ctime.t_nsec);
to->di_size = be64_to_cpu(from->di_size);
to->di_nblocks = be64_to_cpu(from->di_nblocks);
to->di_extsize = be32_to_cpu(from->di_extsize);
to->di_nextents = be32_to_cpu(from->di_nextents);
to->di_anextents = be16_to_cpu(from->di_anextents);
to->di_forkoff = from->di_forkoff;
to->di_aformat = from->di_aformat;
to->di_dmevmask = be32_to_cpu(from->di_dmevmask);
to->di_dmstate = be16_to_cpu(from->di_dmstate);
to->di_flags = be16_to_cpu(from->di_flags);
to->di_gen = be32_to_cpu(from->di_gen);
}
void
xfs_dinode_to_disk(
xfs_dinode_t *to,
xfs_icdinode_t *from)
{
to->di_magic = cpu_to_be16(from->di_magic);
to->di_mode = cpu_to_be16(from->di_mode);
to->di_version = from ->di_version;
to->di_format = from->di_format;
to->di_onlink = cpu_to_be16(from->di_onlink);
to->di_uid = cpu_to_be32(from->di_uid);
to->di_gid = cpu_to_be32(from->di_gid);
to->di_nlink = cpu_to_be32(from->di_nlink);
to->di_projid_lo = cpu_to_be16(from->di_projid_lo);
to->di_projid_hi = cpu_to_be16(from->di_projid_hi);
memcpy(to->di_pad, from->di_pad, sizeof(to->di_pad));
to->di_flushiter = cpu_to_be16(from->di_flushiter);
to->di_atime.t_sec = cpu_to_be32(from->di_atime.t_sec);
to->di_atime.t_nsec = cpu_to_be32(from->di_atime.t_nsec);
to->di_mtime.t_sec = cpu_to_be32(from->di_mtime.t_sec);
to->di_mtime.t_nsec = cpu_to_be32(from->di_mtime.t_nsec);
to->di_ctime.t_sec = cpu_to_be32(from->di_ctime.t_sec);
to->di_ctime.t_nsec = cpu_to_be32(from->di_ctime.t_nsec);
to->di_size = cpu_to_be64(from->di_size);
to->di_nblocks = cpu_to_be64(from->di_nblocks);
to->di_extsize = cpu_to_be32(from->di_extsize);
to->di_nextents = cpu_to_be32(from->di_nextents);
to->di_anextents = cpu_to_be16(from->di_anextents);
to->di_forkoff = from->di_forkoff;
to->di_aformat = from->di_aformat;
to->di_dmevmask = cpu_to_be32(from->di_dmevmask);
to->di_dmstate = cpu_to_be16(from->di_dmstate);
to->di_flags = cpu_to_be16(from->di_flags);
to->di_gen = cpu_to_be32(from->di_gen);
}
STATIC uint
_xfs_dic2xflags(
__uint16_t di_flags)
{
uint flags = 0;
if (di_flags & XFS_DIFLAG_ANY) {
if (di_flags & XFS_DIFLAG_REALTIME)
flags |= XFS_XFLAG_REALTIME;
if (di_flags & XFS_DIFLAG_PREALLOC)
flags |= XFS_XFLAG_PREALLOC;
if (di_flags & XFS_DIFLAG_IMMUTABLE)
flags |= XFS_XFLAG_IMMUTABLE;
if (di_flags & XFS_DIFLAG_APPEND)
flags |= XFS_XFLAG_APPEND;
if (di_flags & XFS_DIFLAG_SYNC)
flags |= XFS_XFLAG_SYNC;
if (di_flags & XFS_DIFLAG_NOATIME)
flags |= XFS_XFLAG_NOATIME;
if (di_flags & XFS_DIFLAG_NODUMP)
flags |= XFS_XFLAG_NODUMP;
if (di_flags & XFS_DIFLAG_RTINHERIT)
flags |= XFS_XFLAG_RTINHERIT;
if (di_flags & XFS_DIFLAG_PROJINHERIT)
flags |= XFS_XFLAG_PROJINHERIT;
if (di_flags & XFS_DIFLAG_NOSYMLINKS)
flags |= XFS_XFLAG_NOSYMLINKS;
if (di_flags & XFS_DIFLAG_EXTSIZE)
flags |= XFS_XFLAG_EXTSIZE;
if (di_flags & XFS_DIFLAG_EXTSZINHERIT)
flags |= XFS_XFLAG_EXTSZINHERIT;
if (di_flags & XFS_DIFLAG_NODEFRAG)
flags |= XFS_XFLAG_NODEFRAG;
if (di_flags & XFS_DIFLAG_FILESTREAM)
flags |= XFS_XFLAG_FILESTREAM;
}
return flags;
}
uint
xfs_ip2xflags(
xfs_inode_t *ip)
{
xfs_icdinode_t *dic = &ip->i_d;
return _xfs_dic2xflags(dic->di_flags) |
(XFS_IFORK_Q(ip) ? XFS_XFLAG_HASATTR : 0);
}
uint
xfs_dic2xflags(
xfs_dinode_t *dip)
{
return _xfs_dic2xflags(be16_to_cpu(dip->di_flags)) |
(XFS_DFORK_Q(dip) ? XFS_XFLAG_HASATTR : 0);
}
/*
* Read the disk inode attributes into the in-core inode structure.
*/
int
xfs_iread(
xfs_mount_t *mp,
xfs_trans_t *tp,
xfs_inode_t *ip,
uint iget_flags)
{
xfs_buf_t *bp;
xfs_dinode_t *dip;
int error;
/*
* Fill in the location information in the in-core inode.
*/
error = xfs_imap(mp, tp, ip->i_ino, &ip->i_imap, iget_flags);
if (error)
return error;
/*
* Get pointers to the on-disk inode and the buffer containing it.
*/
error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &bp,
XBF_LOCK, iget_flags);
if (error)
return error;
dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
/*
* If we got something that isn't an inode it means someone
* (nfs or dmi) has a stale handle.
*/
if (be16_to_cpu(dip->di_magic) != XFS_DINODE_MAGIC) {
#ifdef DEBUG
xfs_alert(mp,
"%s: dip->di_magic (0x%x) != XFS_DINODE_MAGIC (0x%x)",
__func__, be16_to_cpu(dip->di_magic), XFS_DINODE_MAGIC);
#endif /* DEBUG */
error = XFS_ERROR(EINVAL);
goto out_brelse;
}
/*
* If the on-disk inode is already linked to a directory
* entry, copy all of the inode into the in-core inode.
* xfs_iformat() handles copying in the inode format
* specific information.
* Otherwise, just get the truly permanent information.
*/
if (dip->di_mode) {
xfs_dinode_from_disk(&ip->i_d, dip);
error = xfs_iformat(ip, dip);
if (error) {
#ifdef DEBUG
xfs_alert(mp, "%s: xfs_iformat() returned error %d",
__func__, error);
#endif /* DEBUG */
goto out_brelse;
}
} else {
ip->i_d.di_magic = be16_to_cpu(dip->di_magic);
ip->i_d.di_version = dip->di_version;
ip->i_d.di_gen = be32_to_cpu(dip->di_gen);
ip->i_d.di_flushiter = be16_to_cpu(dip->di_flushiter);
/*
* Make sure to pull in the mode here as well in
* case the inode is released without being used.
* This ensures that xfs_inactive() will see that
* the inode is already free and not try to mess
* with the uninitialized part of it.
*/
ip->i_d.di_mode = 0;
/*
* Initialize the per-fork minima and maxima for a new
* inode here. xfs_iformat will do it for old inodes.
*/
ip->i_df.if_ext_max =
XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
}
/*
* The inode format changed when we moved the link count and
* made it 32 bits long. If this is an old format inode,
* convert it in memory to look like a new one. If it gets
* flushed to disk we will convert back before flushing or
* logging it. We zero out the new projid field and the old link
* count field. We'll handle clearing the pad field (the remains
* of the old uuid field) when we actually convert the inode to
* the new format. We don't change the version number so that we
* can distinguish this from a real new format inode.
*/
if (ip->i_d.di_version == 1) {
ip->i_d.di_nlink = ip->i_d.di_onlink;
ip->i_d.di_onlink = 0;
xfs_set_projid(ip, 0);
}
ip->i_delayed_blks = 0;
ip->i_size = ip->i_d.di_size;
/*
* Mark the buffer containing the inode as something to keep
* around for a while. This helps to keep recently accessed
* meta-data in-core longer.
*/
xfs_buf_set_ref(bp, XFS_INO_REF);
/*
* Use xfs_trans_brelse() to release the buffer containing the
* on-disk inode, because it was acquired with xfs_trans_read_buf()
* in xfs_itobp() above. If tp is NULL, this is just a normal
* brelse(). If we're within a transaction, then xfs_trans_brelse()
* will only release the buffer if it is not dirty within the
* transaction. It will be OK to release the buffer in this case,
* because inodes on disk are never destroyed and we will be
* locking the new in-core inode before putting it in the hash
* table where other processes can find it. Thus we don't have
* to worry about the inode being changed just because we released
* the buffer.
*/
out_brelse:
xfs_trans_brelse(tp, bp);
return error;
}
/*
* Read in extents from a btree-format inode.
* Allocate and fill in if_extents. Real work is done in xfs_bmap.c.
*/
int
xfs_iread_extents(
xfs_trans_t *tp,
xfs_inode_t *ip,
int whichfork)
{
int error;
xfs_ifork_t *ifp;
xfs_extnum_t nextents;
if (unlikely(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) {
XFS_ERROR_REPORT("xfs_iread_extents", XFS_ERRLEVEL_LOW,
ip->i_mount);
return XFS_ERROR(EFSCORRUPTED);
}
nextents = XFS_IFORK_NEXTENTS(ip, whichfork);
ifp = XFS_IFORK_PTR(ip, whichfork);
/*
* We know that the size is valid (it's checked in iformat_btree)
*/
ifp->if_lastex = NULLEXTNUM;
ifp->if_bytes = ifp->if_real_bytes = 0;
ifp->if_flags |= XFS_IFEXTENTS;
xfs_iext_add(ifp, 0, nextents);
error = xfs_bmap_read_extents(tp, ip, whichfork);
if (error) {
xfs_iext_destroy(ifp);
ifp->if_flags &= ~XFS_IFEXTENTS;
return error;
}
xfs_validate_extents(ifp, nextents, XFS_EXTFMT_INODE(ip));
return 0;
}
/*
* Allocate an inode on disk and return a copy of its in-core version.
* The in-core inode is locked exclusively. Set mode, nlink, and rdev
* appropriately within the inode. The uid and gid for the inode are
* set according to the contents of the given cred structure.
*
* Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
* has a free inode available, call xfs_iget()
* to obtain the in-core version of the allocated inode. Finally,
* fill in the inode and log its initial contents. In this case,
* ialloc_context would be set to NULL and call_again set to false.
*
* If xfs_dialloc() does not have an available inode,
* it will replenish its supply by doing an allocation. Since we can
* only do one allocation within a transaction without deadlocks, we
* must commit the current transaction before returning the inode itself.
* In this case, therefore, we will set call_again to true and return.
* The caller should then commit the current transaction, start a new
* transaction, and call xfs_ialloc() again to actually get the inode.
*
* To ensure that some other process does not grab the inode that
* was allocated during the first call to xfs_ialloc(), this routine
* also returns the [locked] bp pointing to the head of the freelist
* as ialloc_context. The caller should hold this buffer across
* the commit and pass it back into this routine on the second call.
*
* If we are allocating quota inodes, we do not have a parent inode
* to attach to or associate with (i.e. pip == NULL) because they
* are not linked into the directory structure - they are attached
* directly to the superblock - and so have no parent.
*/
int
xfs_ialloc(
xfs_trans_t *tp,
xfs_inode_t *pip,
mode_t mode,
xfs_nlink_t nlink,
xfs_dev_t rdev,
prid_t prid,
int okalloc,
xfs_buf_t **ialloc_context,
boolean_t *call_again,
xfs_inode_t **ipp)
{
xfs_ino_t ino;
xfs_inode_t *ip;
uint flags;
int error;
timespec_t tv;
int filestreams = 0;
/*
* Call the space management code to pick
* the on-disk inode to be allocated.
*/
error = xfs_dialloc(tp, pip ? pip->i_ino : 0, mode, okalloc,
ialloc_context, call_again, &ino);
if (error)
return error;
if (*call_again || ino == NULLFSINO) {
*ipp = NULL;
return 0;
}
ASSERT(*ialloc_context == NULL);
/*
* Get the in-core inode with the lock held exclusively.
* This is because we're setting fields here we need
* to prevent others from looking at until we're done.
*/
error = xfs_iget(tp->t_mountp, tp, ino, XFS_IGET_CREATE,
XFS_ILOCK_EXCL, &ip);
if (error)
return error;
ASSERT(ip != NULL);
ip->i_d.di_mode = (__uint16_t)mode;
ip->i_d.di_onlink = 0;
ip->i_d.di_nlink = nlink;
ASSERT(ip->i_d.di_nlink == nlink);
ip->i_d.di_uid = current_fsuid();
ip->i_d.di_gid = current_fsgid();
xfs_set_projid(ip, prid);
memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
/*
* If the superblock version is up to where we support new format
* inodes and this is currently an old format inode, then change
* the inode version number now. This way we only do the conversion
* here rather than here and in the flush/logging code.
*/
if (xfs_sb_version_hasnlink(&tp->t_mountp->m_sb) &&
ip->i_d.di_version == 1) {
ip->i_d.di_version = 2;
/*
* We've already zeroed the old link count, the projid field,
* and the pad field.
*/
}
/*
* Project ids won't be stored on disk if we are using a version 1 inode.
*/
if ((prid != 0) && (ip->i_d.di_version == 1))
xfs_bump_ino_vers2(tp, ip);
if (pip && XFS_INHERIT_GID(pip)) {
ip->i_d.di_gid = pip->i_d.di_gid;
if ((pip->i_d.di_mode & S_ISGID) && (mode & S_IFMT) == S_IFDIR) {
ip->i_d.di_mode |= S_ISGID;
}
}
/*
* If the group ID of the new file does not match the effective group
* ID or one of the supplementary group IDs, the S_ISGID bit is cleared
* (and only if the irix_sgid_inherit compatibility variable is set).
*/
if ((irix_sgid_inherit) &&
(ip->i_d.di_mode & S_ISGID) &&
(!in_group_p((gid_t)ip->i_d.di_gid))) {
ip->i_d.di_mode &= ~S_ISGID;
}
ip->i_d.di_size = 0;
ip->i_size = 0;
ip->i_d.di_nextents = 0;
ASSERT(ip->i_d.di_nblocks == 0);
nanotime(&tv);
ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec;
ip->i_d.di_mtime.t_nsec = (__int32_t)tv.tv_nsec;
ip->i_d.di_atime = ip->i_d.di_mtime;
ip->i_d.di_ctime = ip->i_d.di_mtime;
/*
* di_gen will have been taken care of in xfs_iread.
*/
ip->i_d.di_extsize = 0;
ip->i_d.di_dmevmask = 0;
ip->i_d.di_dmstate = 0;
ip->i_d.di_flags = 0;
flags = XFS_ILOG_CORE;
switch (mode & S_IFMT) {
case S_IFIFO:
case S_IFCHR:
case S_IFBLK:
case S_IFSOCK:
ip->i_d.di_format = XFS_DINODE_FMT_DEV;
ip->i_df.if_u2.if_rdev = rdev;
ip->i_df.if_flags = 0;
flags |= XFS_ILOG_DEV;
break;
case S_IFREG:
/*
* we can't set up filestreams until after the VFS inode
* is set up properly.
*/
if (pip && xfs_inode_is_filestream(pip))
filestreams = 1;
/* fall through */
case S_IFDIR:
if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
uint di_flags = 0;
if ((mode & S_IFMT) == S_IFDIR) {
if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
di_flags |= XFS_DIFLAG_RTINHERIT;
if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
di_flags |= XFS_DIFLAG_EXTSZINHERIT;
ip->i_d.di_extsize = pip->i_d.di_extsize;
}
} else if ((mode & S_IFMT) == S_IFREG) {
if (pip->i_d.di_flags & XFS_DIFLAG_RTINHERIT)
di_flags |= XFS_DIFLAG_REALTIME;
if (pip->i_d.di_flags & XFS_DIFLAG_EXTSZINHERIT) {
di_flags |= XFS_DIFLAG_EXTSIZE;
ip->i_d.di_extsize = pip->i_d.di_extsize;
}
}
if ((pip->i_d.di_flags & XFS_DIFLAG_NOATIME) &&
xfs_inherit_noatime)
di_flags |= XFS_DIFLAG_NOATIME;
if ((pip->i_d.di_flags & XFS_DIFLAG_NODUMP) &&
xfs_inherit_nodump)
di_flags |= XFS_DIFLAG_NODUMP;
if ((pip->i_d.di_flags & XFS_DIFLAG_SYNC) &&
xfs_inherit_sync)
di_flags |= XFS_DIFLAG_SYNC;
if ((pip->i_d.di_flags & XFS_DIFLAG_NOSYMLINKS) &&
xfs_inherit_nosymlinks)
di_flags |= XFS_DIFLAG_NOSYMLINKS;
if (pip->i_d.di_flags & XFS_DIFLAG_PROJINHERIT)
di_flags |= XFS_DIFLAG_PROJINHERIT;
if ((pip->i_d.di_flags & XFS_DIFLAG_NODEFRAG) &&
xfs_inherit_nodefrag)
di_flags |= XFS_DIFLAG_NODEFRAG;
if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
di_flags |= XFS_DIFLAG_FILESTREAM;
ip->i_d.di_flags |= di_flags;
}
/* FALLTHROUGH */
case S_IFLNK:
ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
ip->i_df.if_flags = XFS_IFEXTENTS;
ip->i_df.if_bytes = ip->i_df.if_real_bytes = 0;
ip->i_df.if_u1.if_extents = NULL;
break;
default:
ASSERT(0);
}
/*
* Attribute fork settings for new inode.
*/
ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
ip->i_d.di_anextents = 0;
/*
* Log the new values stuffed into the inode.
*/
xfs_trans_ijoin_ref(tp, ip, XFS_ILOCK_EXCL);
xfs_trans_log_inode(tp, ip, flags);
/* now that we have an i_mode we can setup inode ops and unlock */
xfs_setup_inode(ip);
/* now we have set up the vfs inode we can associate the filestream */
if (filestreams) {
error = xfs_filestream_associate(pip, ip);
if (error < 0)
return -error;
if (!error)
xfs_iflags_set(ip, XFS_IFILESTREAM);
}
*ipp = ip;
return 0;
}
/*
* Check to make sure that there are no blocks allocated to the
* file beyond the size of the file. We don't check this for
* files with fixed size extents or real time extents, but we
* at least do it for regular files.
*/
#ifdef DEBUG
void
xfs_isize_check(
xfs_mount_t *mp,
xfs_inode_t *ip,
xfs_fsize_t isize)
{
xfs_fileoff_t map_first;
int nimaps;
xfs_bmbt_irec_t imaps[2];
if ((ip->i_d.di_mode & S_IFMT) != S_IFREG)
return;
if (XFS_IS_REALTIME_INODE(ip))
return;
if (ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE)
return;
nimaps = 2;
map_first = XFS_B_TO_FSB(mp, (xfs_ufsize_t)isize);
/*
* The filesystem could be shutting down, so bmapi may return
* an error.
*/
if (xfs_bmapi(NULL, ip, map_first,
(XFS_B_TO_FSB(mp,
(xfs_ufsize_t)XFS_MAXIOFFSET(mp)) -
map_first),
XFS_BMAPI_ENTIRE, NULL, 0, imaps, &nimaps,
NULL))
return;
ASSERT(nimaps == 1);
ASSERT(imaps[0].br_startblock == HOLESTARTBLOCK);
}
#endif /* DEBUG */
/*
* Calculate the last possible buffered byte in a file. This must
* include data that was buffered beyond the EOF by the write code.
* This also needs to deal with overflowing the xfs_fsize_t type
* which can happen for sizes near the limit.
*
* We also need to take into account any blocks beyond the EOF. It
* may be the case that they were buffered by a write which failed.
* In that case the pages will still be in memory, but the inode size
* will never have been updated.
*/
STATIC xfs_fsize_t
xfs_file_last_byte(
xfs_inode_t *ip)
{
xfs_mount_t *mp;
xfs_fsize_t last_byte;
xfs_fileoff_t last_block;
xfs_fileoff_t size_last_block;
int error;
ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED));
mp = ip->i_mount;
/*
* Only check for blocks beyond the EOF if the extents have
* been read in. This eliminates the need for the inode lock,
* and it also saves us from looking when it really isn't
* necessary.
*/
if (ip->i_df.if_flags & XFS_IFEXTENTS) {
xfs_ilock(ip, XFS_ILOCK_SHARED);
error = xfs_bmap_last_offset(NULL, ip, &last_block,
XFS_DATA_FORK);
xfs_iunlock(ip, XFS_ILOCK_SHARED);
if (error) {
last_block = 0;
}
} else {
last_block = 0;
}
size_last_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)ip->i_size);
last_block = XFS_FILEOFF_MAX(last_block, size_last_block);
last_byte = XFS_FSB_TO_B(mp, last_block);
if (last_byte < 0) {
return XFS_MAXIOFFSET(mp);
}
last_byte += (1 << mp->m_writeio_log);
if (last_byte < 0) {
return XFS_MAXIOFFSET(mp);
}
return last_byte;
}
/*
* Start the truncation of the file to new_size. The new size
* must be smaller than the current size. This routine will
* clear the buffer and page caches of file data in the removed
* range, and xfs_itruncate_finish() will remove the underlying
* disk blocks.
*
* The inode must have its I/O lock locked EXCLUSIVELY, and it
* must NOT have the inode lock held at all. This is because we're
* calling into the buffer/page cache code and we can't hold the
* inode lock when we do so.
*
* We need to wait for any direct I/Os in flight to complete before we
* proceed with the truncate. This is needed to prevent the extents
* being read or written by the direct I/Os from being removed while the
* I/O is in flight as there is no other method of synchronising
* direct I/O with the truncate operation. Also, because we hold
* the IOLOCK in exclusive mode, we prevent new direct I/Os from being
* started until the truncate completes and drops the lock. Essentially,
* the xfs_ioend_wait() call forms an I/O barrier that provides strict
* ordering between direct I/Os and the truncate operation.
*
* The flags parameter can have either the value XFS_ITRUNC_DEFINITE
* or XFS_ITRUNC_MAYBE. The XFS_ITRUNC_MAYBE value should be used
* in the case that the caller is locking things out of order and
* may not be able to call xfs_itruncate_finish() with the inode lock
* held without dropping the I/O lock. If the caller must drop the
* I/O lock before calling xfs_itruncate_finish(), then xfs_itruncate_start()
* must be called again with all the same restrictions as the initial
* call.
*/
int
xfs_itruncate_start(
xfs_inode_t *ip,
uint flags,
xfs_fsize_t new_size)
{
xfs_fsize_t last_byte;
xfs_off_t toss_start;
xfs_mount_t *mp;
int error = 0;
ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
ASSERT((new_size == 0) || (new_size <= ip->i_size));
ASSERT((flags == XFS_ITRUNC_DEFINITE) ||
(flags == XFS_ITRUNC_MAYBE));
mp = ip->i_mount;
/* wait for the completion of any pending DIOs */
if (new_size == 0 || new_size < ip->i_size)
xfs_ioend_wait(ip);
/*
* Call toss_pages or flushinval_pages to get rid of pages
* overlapping the region being removed. We have to use
* the less efficient flushinval_pages in the case that the
* caller may not be able to finish the truncate without
* dropping the inode's I/O lock. Make sure
* to catch any pages brought in by buffers overlapping
* the EOF by searching out beyond the isize by our
* block size. We round new_size up to a block boundary
* so that we don't toss things on the same block as
* new_size but before it.
*
* Before calling toss_page or flushinval_pages, make sure to
* call remapf() over the same region if the file is mapped.
* This frees up mapped file references to the pages in the
* given range and for the flushinval_pages case it ensures
* that we get the latest mapped changes flushed out.
*/
toss_start = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
toss_start = XFS_FSB_TO_B(mp, toss_start);
if (toss_start < 0) {
/*
* The place to start tossing is beyond our maximum
* file size, so there is no way that the data extended
* out there.
*/
return 0;
}
last_byte = xfs_file_last_byte(ip);
trace_xfs_itruncate_start(ip, new_size, flags, toss_start, last_byte);
if (last_byte > toss_start) {
if (flags & XFS_ITRUNC_DEFINITE) {
xfs_tosspages(ip, toss_start,
-1, FI_REMAPF_LOCKED);
} else {
error = xfs_flushinval_pages(ip, toss_start,
-1, FI_REMAPF_LOCKED);
}
}
#ifdef DEBUG
if (new_size == 0) {
ASSERT(VN_CACHED(VFS_I(ip)) == 0);
}
#endif
return error;
}
/*
* Shrink the file to the given new_size. The new size must be smaller than
* the current size. This will free up the underlying blocks in the removed
* range after a call to xfs_itruncate_start() or xfs_atruncate_start().
*
* The transaction passed to this routine must have made a permanent log
* reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
* given transaction and start new ones, so make sure everything involved in
* the transaction is tidy before calling here. Some transaction will be
* returned to the caller to be committed. The incoming transaction must
* already include the inode, and both inode locks must be held exclusively.
* The inode must also be "held" within the transaction. On return the inode
* will be "held" within the returned transaction. This routine does NOT
* require any disk space to be reserved for it within the transaction.
*
* The fork parameter must be either xfs_attr_fork or xfs_data_fork, and it
* indicates the fork which is to be truncated. For the attribute fork we only
* support truncation to size 0.
*
* We use the sync parameter to indicate whether or not the first transaction
* we perform might have to be synchronous. For the attr fork, it needs to be
* so if the unlink of the inode is not yet known to be permanent in the log.
* This keeps us from freeing and reusing the blocks of the attribute fork
* before the unlink of the inode becomes permanent.
*
* For the data fork, we normally have to run synchronously if we're being
* called out of the inactive path or we're being called out of the create path
* where we're truncating an existing file. Either way, the truncate needs to
* be sync so blocks don't reappear in the file with altered data in case of a
* crash. wsync filesystems can run the first case async because anything that
* shrinks the inode has to run sync so by the time we're called here from
* inactive, the inode size is permanently set to 0.
*
* Calls from the truncate path always need to be sync unless we're in a wsync
* filesystem and the file has already been unlinked.
*
* The caller is responsible for correctly setting the sync parameter. It gets
* too hard for us to guess here which path we're being called out of just
* based on inode state.
*
* If we get an error, we must return with the inode locked and linked into the
* current transaction. This keeps things simple for the higher level code,
* because it always knows that the inode is locked and held in the transaction
* that returns to it whether errors occur or not. We don't mark the inode
* dirty on error so that transactions can be easily aborted if possible.
*/
int
xfs_itruncate_finish(
xfs_trans_t **tp,
xfs_inode_t *ip,
xfs_fsize_t new_size,
int fork,
int sync)
{
xfs_fsblock_t first_block;
xfs_fileoff_t first_unmap_block;
xfs_fileoff_t last_block;
xfs_filblks_t unmap_len=0;
xfs_mount_t *mp;
xfs_trans_t *ntp;
int done;
int committed;
xfs_bmap_free_t free_list;
int error;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL));
ASSERT((new_size == 0) || (new_size <= ip->i_size));
ASSERT(*tp != NULL);
ASSERT((*tp)->t_flags & XFS_TRANS_PERM_LOG_RES);
ASSERT(ip->i_transp == *tp);
ASSERT(ip->i_itemp != NULL);
ASSERT(ip->i_itemp->ili_lock_flags == 0);
ntp = *tp;
mp = (ntp)->t_mountp;
ASSERT(! XFS_NOT_DQATTACHED(mp, ip));
/*
* We only support truncating the entire attribute fork.
*/
if (fork == XFS_ATTR_FORK) {
new_size = 0LL;
}
first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size);
trace_xfs_itruncate_finish_start(ip, new_size);
/*
* The first thing we do is set the size to new_size permanently
* on disk. This way we don't have to worry about anyone ever
* being able to look at the data being freed even in the face
* of a crash. What we're getting around here is the case where
* we free a block, it is allocated to another file, it is written
* to, and then we crash. If the new data gets written to the
* file but the log buffers containing the free and reallocation
* don't, then we'd end up with garbage in the blocks being freed.
* As long as we make the new_size permanent before actually
* freeing any blocks it doesn't matter if they get written to.
*
* The callers must signal into us whether or not the size
* setting here must be synchronous. There are a few cases
* where it doesn't have to be synchronous. Those cases
* occur if the file is unlinked and we know the unlink is
* permanent or if the blocks being truncated are guaranteed
* to be beyond the inode eof (regardless of the link count)
* and the eof value is permanent. Both of these cases occur
* only on wsync-mounted filesystems. In those cases, we're
* guaranteed that no user will ever see the data in the blocks
* that are being truncated so the truncate can run async.
* In the free beyond eof case, the file may wind up with
* more blocks allocated to it than it needs if we crash
* and that won't get fixed until the next time the file
* is re-opened and closed but that's ok as that shouldn't
* be too many blocks.
*
* However, we can't just make all wsync xactions run async
* because there's one call out of the create path that needs
* to run sync where it's truncating an existing file to size
* 0 whose size is > 0.
*
* It's probably possible to come up with a test in this
* routine that would correctly distinguish all the above
* cases from the values of the function parameters and the
* inode state but for sanity's sake, I've decided to let the
* layers above just tell us. It's simpler to correctly figure
* out in the layer above exactly under what conditions we
* can run async and I think it's easier for others read and
* follow the logic in case something has to be changed.
* cscope is your friend -- rcc.
*
* The attribute fork is much simpler.
*
* For the attribute fork we allow the caller to tell us whether
* the unlink of the inode that led to this call is yet permanent
* in the on disk log. If it is not and we will be freeing extents
* in this inode then we make the first transaction synchronous
* to make sure that the unlink is permanent by the time we free
* the blocks.
*/
if (fork == XFS_DATA_FORK) {
if (ip->i_d.di_nextents > 0) {
/*
* If we are not changing the file size then do
* not update the on-disk file size - we may be
* called from xfs_inactive_free_eofblocks(). If we
* update the on-disk file size and then the system
* crashes before the contents of the file are
* flushed to disk then the files may be full of
* holes (ie NULL files bug).
*/
if (ip->i_size != new_size) {
ip->i_d.di_size = new_size;
ip->i_size = new_size;
xfs_trans_log_inode(ntp, ip, XFS_ILOG_CORE);
}
}
} else if (sync) {
ASSERT(!(mp->m_flags & XFS_MOUNT_WSYNC));
if (ip->i_d.di_anextents > 0)
xfs_trans_set_sync(ntp);
}
ASSERT(fork == XFS_DATA_FORK ||
(fork == XFS_ATTR_FORK &&
((sync && !(mp->m_flags & XFS_MOUNT_WSYNC)) ||
(sync == 0 && (mp->m_flags & XFS_MOUNT_WSYNC)))));
/*
* Since it is possible for space to become allocated beyond
* the end of the file (in a crash where the space is allocated
* but the inode size is not yet updated), simply remove any
* blocks which show up between the new EOF and the maximum
* possible file size. If the first block to be removed is
* beyond the maximum file size (ie it is the same as last_block),
* then there is nothing to do.
*/
last_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_MAXIOFFSET(mp));
ASSERT(first_unmap_block <= last_block);
done = 0;
if (last_block == first_unmap_block) {
done = 1;
} else {
unmap_len = last_block - first_unmap_block + 1;
}
while (!done) {
/*
* Free up up to XFS_ITRUNC_MAX_EXTENTS. xfs_bunmapi()
* will tell us whether it freed the entire range or
* not. If this is a synchronous mount (wsync),
* then we can tell bunmapi to keep all the
* transactions asynchronous since the unlink
* transaction that made this inode inactive has
* already hit the disk. There's no danger of
* the freed blocks being reused, there being a
* crash, and the reused blocks suddenly reappearing
* in this file with garbage in them once recovery
* runs.
*/
xfs_bmap_init(&free_list, &first_block);
error = xfs_bunmapi(ntp, ip,
first_unmap_block, unmap_len,
xfs_bmapi_aflag(fork),
XFS_ITRUNC_MAX_EXTENTS,
&first_block, &free_list,
&done);
if (error) {
/*
* If the bunmapi call encounters an error,
* return to the caller where the transaction
* can be properly aborted. We just need to
* make sure we're not holding any resources
* that we were not when we came in.
*/
xfs_bmap_cancel(&free_list);
return error;
}
/*
* Duplicate the transaction that has the permanent
* reservation and commit the old transaction.
*/
error = xfs_bmap_finish(tp, &free_list, &committed);
ntp = *tp;
if (committed)
xfs_trans_ijoin(ntp, ip);
if (error) {
/*
* If the bmap finish call encounters an error, return
* to the caller where the transaction can be properly
* aborted. We just need to make sure we're not
* holding any resources that we were not when we came
* in.
*
* Aborting from this point might lose some blocks in
* the file system, but oh well.
*/
xfs_bmap_cancel(&free_list);
return error;
}
if (committed) {
/*
* Mark the inode dirty so it will be logged and
* moved forward in the log as part of every commit.
*/
xfs_trans_log_inode(ntp, ip, XFS_ILOG_CORE);
}
ntp = xfs_trans_dup(ntp);
error = xfs_trans_commit(*tp, 0);
*tp = ntp;
xfs_trans_ijoin(ntp, ip);
if (error)
return error;
/*
* transaction commit worked ok so we can drop the extra ticket
* reference that we gained in xfs_trans_dup()
*/
xfs_log_ticket_put(ntp->t_ticket);
error = xfs_trans_reserve(ntp, 0,
XFS_ITRUNCATE_LOG_RES(mp), 0,
XFS_TRANS_PERM_LOG_RES,
XFS_ITRUNCATE_LOG_COUNT);
if (error)
return error;
}
/*
* Only update the size in the case of the data fork, but
* always re-log the inode so that our permanent transaction
* can keep on rolling it forward in the log.
*/
if (fork == XFS_DATA_FORK) {
xfs_isize_check(mp, ip, new_size);
/*
* If we are not changing the file size then do
* not update the on-disk file size - we may be
* called from xfs_inactive_free_eofblocks(). If we
* update the on-disk file size and then the system
* crashes before the contents of the file are
* flushed to disk then the files may be full of
* holes (ie NULL files bug).
*/
if (ip->i_size != new_size) {
ip->i_d.di_size = new_size;
ip->i_size = new_size;
}
}
xfs_trans_log_inode(ntp, ip, XFS_ILOG_CORE);
ASSERT((new_size != 0) ||
(fork == XFS_ATTR_FORK) ||
(ip->i_delayed_blks == 0));
ASSERT((new_size != 0) ||
(fork == XFS_ATTR_FORK) ||
(ip->i_d.di_nextents == 0));
trace_xfs_itruncate_finish_end(ip, new_size);
return 0;
}
/*
* This is called when the inode's link count goes to 0.
* We place the on-disk inode on a list in the AGI. It
* will be pulled from this list when the inode is freed.
*/
int
xfs_iunlink(
xfs_trans_t *tp,
xfs_inode_t *ip)
{
xfs_mount_t *mp;
xfs_agi_t *agi;
xfs_dinode_t *dip;
xfs_buf_t *agibp;
xfs_buf_t *ibp;
xfs_agino_t agino;
short bucket_index;
int offset;
int error;
ASSERT(ip->i_d.di_nlink == 0);
ASSERT(ip->i_d.di_mode != 0);
ASSERT(ip->i_transp == tp);
mp = tp->t_mountp;
/*
* Get the agi buffer first. It ensures lock ordering
* on the list.
*/
error = xfs_read_agi(mp, tp, XFS_INO_TO_AGNO(mp, ip->i_ino), &agibp);
if (error)
return error;
agi = XFS_BUF_TO_AGI(agibp);
/*
* Get the index into the agi hash table for the
* list this inode will go on.
*/
agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
ASSERT(agino != 0);
bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
ASSERT(agi->agi_unlinked[bucket_index]);
ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
if (be32_to_cpu(agi->agi_unlinked[bucket_index]) != NULLAGINO) {
/*
* There is already another inode in the bucket we need
* to add ourselves to. Add us at the front of the list.
* Here we put the head pointer into our next pointer,
* and then we fall through to point the head at us.
*/
error = xfs_itobp(mp, tp, ip, &dip, &ibp, XBF_LOCK);
if (error)
return error;
ASSERT(be32_to_cpu(dip->di_next_unlinked) == NULLAGINO);
/* both on-disk, don't endian flip twice */
dip->di_next_unlinked = agi->agi_unlinked[bucket_index];
offset = ip->i_imap.im_boffset +
offsetof(xfs_dinode_t, di_next_unlinked);
xfs_trans_inode_buf(tp, ibp);
xfs_trans_log_buf(tp, ibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
xfs_inobp_check(mp, ibp);
}
/*
* Point the bucket head pointer at the inode being inserted.
*/
ASSERT(agino != 0);
agi->agi_unlinked[bucket_index] = cpu_to_be32(agino);
offset = offsetof(xfs_agi_t, agi_unlinked) +
(sizeof(xfs_agino_t) * bucket_index);
xfs_trans_log_buf(tp, agibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
return 0;
}
/*
* Pull the on-disk inode from the AGI unlinked list.
*/
STATIC int
xfs_iunlink_remove(
xfs_trans_t *tp,
xfs_inode_t *ip)
{
xfs_ino_t next_ino;
xfs_mount_t *mp;
xfs_agi_t *agi;
xfs_dinode_t *dip;
xfs_buf_t *agibp;
xfs_buf_t *ibp;
xfs_agnumber_t agno;
xfs_agino_t agino;
xfs_agino_t next_agino;
xfs_buf_t *last_ibp;
xfs_dinode_t *last_dip = NULL;
short bucket_index;
int offset, last_offset = 0;
int error;
mp = tp->t_mountp;
agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
/*
* Get the agi buffer first. It ensures lock ordering
* on the list.
*/
error = xfs_read_agi(mp, tp, agno, &agibp);
if (error)
return error;
agi = XFS_BUF_TO_AGI(agibp);
/*
* Get the index into the agi hash table for the
* list this inode will go on.
*/
agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
ASSERT(agino != 0);
bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != NULLAGINO);
ASSERT(agi->agi_unlinked[bucket_index]);
if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
/*
* We're at the head of the list. Get the inode's
* on-disk buffer to see if there is anyone after us
* on the list. Only modify our next pointer if it
* is not already NULLAGINO. This saves us the overhead
* of dealing with the buffer when there is no need to
* change it.
*/
error = xfs_itobp(mp, tp, ip, &dip, &ibp, XBF_LOCK);
if (error) {
xfs_warn(mp, "%s: xfs_itobp() returned error %d.",
__func__, error);
return error;
}
next_agino = be32_to_cpu(dip->di_next_unlinked);
ASSERT(next_agino != 0);
if (next_agino != NULLAGINO) {
dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
offset = ip->i_imap.im_boffset +
offsetof(xfs_dinode_t, di_next_unlinked);
xfs_trans_inode_buf(tp, ibp);
xfs_trans_log_buf(tp, ibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
xfs_inobp_check(mp, ibp);
} else {
xfs_trans_brelse(tp, ibp);
}
/*
* Point the bucket head pointer at the next inode.
*/
ASSERT(next_agino != 0);
ASSERT(next_agino != agino);
agi->agi_unlinked[bucket_index] = cpu_to_be32(next_agino);
offset = offsetof(xfs_agi_t, agi_unlinked) +
(sizeof(xfs_agino_t) * bucket_index);
xfs_trans_log_buf(tp, agibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
} else {
/*
* We need to search the list for the inode being freed.
*/
next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
last_ibp = NULL;
while (next_agino != agino) {
/*
* If the last inode wasn't the one pointing to
* us, then release its buffer since we're not
* going to do anything with it.
*/
if (last_ibp != NULL) {
xfs_trans_brelse(tp, last_ibp);
}
next_ino = XFS_AGINO_TO_INO(mp, agno, next_agino);
error = xfs_inotobp(mp, tp, next_ino, &last_dip,
&last_ibp, &last_offset, 0);
if (error) {
xfs_warn(mp,
"%s: xfs_inotobp() returned error %d.",
__func__, error);
return error;
}
next_agino = be32_to_cpu(last_dip->di_next_unlinked);
ASSERT(next_agino != NULLAGINO);
ASSERT(next_agino != 0);
}
/*
* Now last_ibp points to the buffer previous to us on
* the unlinked list. Pull us from the list.
*/
error = xfs_itobp(mp, tp, ip, &dip, &ibp, XBF_LOCK);
if (error) {
xfs_warn(mp, "%s: xfs_itobp(2) returned error %d.",
__func__, error);
return error;
}
next_agino = be32_to_cpu(dip->di_next_unlinked);
ASSERT(next_agino != 0);
ASSERT(next_agino != agino);
if (next_agino != NULLAGINO) {
dip->di_next_unlinked = cpu_to_be32(NULLAGINO);
offset = ip->i_imap.im_boffset +
offsetof(xfs_dinode_t, di_next_unlinked);
xfs_trans_inode_buf(tp, ibp);
xfs_trans_log_buf(tp, ibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
xfs_inobp_check(mp, ibp);
} else {
xfs_trans_brelse(tp, ibp);
}
/*
* Point the previous inode on the list to the next inode.
*/
last_dip->di_next_unlinked = cpu_to_be32(next_agino);
ASSERT(next_agino != 0);
offset = last_offset + offsetof(xfs_dinode_t, di_next_unlinked);
xfs_trans_inode_buf(tp, last_ibp);
xfs_trans_log_buf(tp, last_ibp, offset,
(offset + sizeof(xfs_agino_t) - 1));
xfs_inobp_check(mp, last_ibp);
}
return 0;
}
/*
* A big issue when freeing the inode cluster is is that we _cannot_ skip any
* inodes that are in memory - they all must be marked stale and attached to
* the cluster buffer.
*/
STATIC void
xfs_ifree_cluster(
xfs_inode_t *free_ip,
xfs_trans_t *tp,
xfs_ino_t inum)
{
xfs_mount_t *mp = free_ip->i_mount;
int blks_per_cluster;
int nbufs;
int ninodes;
int i, j;
xfs_daddr_t blkno;
xfs_buf_t *bp;
xfs_inode_t *ip;
xfs_inode_log_item_t *iip;
xfs_log_item_t *lip;
struct xfs_perag *pag;
pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, inum));
if (mp->m_sb.sb_blocksize >= XFS_INODE_CLUSTER_SIZE(mp)) {
blks_per_cluster = 1;
ninodes = mp->m_sb.sb_inopblock;
nbufs = XFS_IALLOC_BLOCKS(mp);
} else {
blks_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) /
mp->m_sb.sb_blocksize;
ninodes = blks_per_cluster * mp->m_sb.sb_inopblock;
nbufs = XFS_IALLOC_BLOCKS(mp) / blks_per_cluster;
}
for (j = 0; j < nbufs; j++, inum += ninodes) {
blkno = XFS_AGB_TO_DADDR(mp, XFS_INO_TO_AGNO(mp, inum),
XFS_INO_TO_AGBNO(mp, inum));
/*
* We obtain and lock the backing buffer first in the process
* here, as we have to ensure that any dirty inode that we
* can't get the flush lock on is attached to the buffer.
* If we scan the in-memory inodes first, then buffer IO can
* complete before we get a lock on it, and hence we may fail
* to mark all the active inodes on the buffer stale.
*/
bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, blkno,
mp->m_bsize * blks_per_cluster,
XBF_LOCK);
/*
* Walk the inodes already attached to the buffer and mark them
* stale. These will all have the flush locks held, so an
* in-memory inode walk can't lock them. By marking them all
* stale first, we will not attempt to lock them in the loop
* below as the XFS_ISTALE flag will be set.
*/
lip = XFS_BUF_FSPRIVATE(bp, xfs_log_item_t *);
while (lip) {
if (lip->li_type == XFS_LI_INODE) {
iip = (xfs_inode_log_item_t *)lip;
ASSERT(iip->ili_logged == 1);
lip->li_cb = xfs_istale_done;
xfs_trans_ail_copy_lsn(mp->m_ail,
&iip->ili_flush_lsn,
&iip->ili_item.li_lsn);
xfs_iflags_set(iip->ili_inode, XFS_ISTALE);
}
lip = lip->li_bio_list;
}
/*
* For each inode in memory attempt to add it to the inode
* buffer and set it up for being staled on buffer IO
* completion. This is safe as we've locked out tail pushing
* and flushing by locking the buffer.
*
* We have already marked every inode that was part of a
* transaction stale above, which means there is no point in
* even trying to lock them.
*/
for (i = 0; i < ninodes; i++) {
retry:
rcu_read_lock();
ip = radix_tree_lookup(&pag->pag_ici_root,
XFS_INO_TO_AGINO(mp, (inum + i)));
/* Inode not in memory, nothing to do */
if (!ip) {
rcu_read_unlock();
continue;
}
/*
* because this is an RCU protected lookup, we could
* find a recently freed or even reallocated inode
* during the lookup. We need to check under the
* i_flags_lock for a valid inode here. Skip it if it
* is not valid, the wrong inode or stale.
*/
spin_lock(&ip->i_flags_lock);
if (ip->i_ino != inum + i ||
__xfs_iflags_test(ip, XFS_ISTALE)) {
spin_unlock(&ip->i_flags_lock);
rcu_read_unlock();
continue;
}
spin_unlock(&ip->i_flags_lock);
/*
* Don't try to lock/unlock the current inode, but we
* _cannot_ skip the other inodes that we did not find
* in the list attached to the buffer and are not
* already marked stale. If we can't lock it, back off
* and retry.
*/
if (ip != free_ip &&
!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
rcu_read_unlock();
delay(1);
goto retry;
}
rcu_read_unlock();
xfs_iflock(ip);
xfs_iflags_set(ip, XFS_ISTALE);
/*
* we don't need to attach clean inodes or those only
* with unlogged changes (which we throw away, anyway).
*/
iip = ip->i_itemp;
if (!iip || xfs_inode_clean(ip)) {
ASSERT(ip != free_ip);
ip->i_update_core = 0;
xfs_ifunlock(ip);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
continue;
}
iip->ili_last_fields = iip->ili_format.ilf_fields;
iip->ili_format.ilf_fields = 0;
iip->ili_logged = 1;
xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
&iip->ili_item.li_lsn);
xfs_buf_attach_iodone(bp, xfs_istale_done,
&iip->ili_item);
if (ip != free_ip)
xfs_iunlock(ip, XFS_ILOCK_EXCL);
}
xfs_trans_stale_inode_buf(tp, bp);
xfs_trans_binval(tp, bp);
}
xfs_perag_put(pag);
}
/*
* This is called to return an inode to the inode free list.
* The inode should already be truncated to 0 length and have
* no pages associated with it. This routine also assumes that
* the inode is already a part of the transaction.
*
* The on-disk copy of the inode will have been added to the list
* of unlinked inodes in the AGI. We need to remove the inode from
* that list atomically with respect to freeing it here.
*/
int
xfs_ifree(
xfs_trans_t *tp,
xfs_inode_t *ip,
xfs_bmap_free_t *flist)
{
int error;
int delete;
xfs_ino_t first_ino;
xfs_dinode_t *dip;
xfs_buf_t *ibp;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(ip->i_transp == tp);
ASSERT(ip->i_d.di_nlink == 0);
ASSERT(ip->i_d.di_nextents == 0);
ASSERT(ip->i_d.di_anextents == 0);
ASSERT((ip->i_d.di_size == 0 && ip->i_size == 0) ||
((ip->i_d.di_mode & S_IFMT) != S_IFREG));
ASSERT(ip->i_d.di_nblocks == 0);
/*
* Pull the on-disk inode from the AGI unlinked list.
*/
error = xfs_iunlink_remove(tp, ip);
if (error != 0) {
return error;
}
error = xfs_difree(tp, ip->i_ino, flist, &delete, &first_ino);
if (error != 0) {
return error;
}
ip->i_d.di_mode = 0; /* mark incore inode as free */
ip->i_d.di_flags = 0;
ip->i_d.di_dmevmask = 0;
ip->i_d.di_forkoff = 0; /* mark the attr fork not in use */
ip->i_df.if_ext_max =
XFS_IFORK_DSIZE(ip) / (uint)sizeof(xfs_bmbt_rec_t);
ip->i_d.di_format = XFS_DINODE_FMT_EXTENTS;
ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;
/*
* Bump the generation count so no one will be confused
* by reincarnations of this inode.
*/
ip->i_d.di_gen++;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
error = xfs_itobp(ip->i_mount, tp, ip, &dip, &ibp, XBF_LOCK);
if (error)
return error;
/*
* Clear the on-disk di_mode. This is to prevent xfs_bulkstat
* from picking up this inode when it is reclaimed (its incore state
* initialzed but not flushed to disk yet). The in-core di_mode is
* already cleared and a corresponding transaction logged.
* The hack here just synchronizes the in-core to on-disk
* di_mode value in advance before the actual inode sync to disk.
* This is OK because the inode is already unlinked and would never
* change its di_mode again for this inode generation.
* This is a temporary hack that would require a proper fix
* in the future.
*/
dip->di_mode = 0;
if (delete) {
xfs_ifree_cluster(ip, tp, first_ino);
}
return 0;
}
/*
* Reallocate the space for if_broot based on the number of records
* being added or deleted as indicated in rec_diff. Move the records
* and pointers in if_broot to fit the new size. When shrinking this
* will eliminate holes between the records and pointers created by
* the caller. When growing this will create holes to be filled in
* by the caller.
*
* The caller must not request to add more records than would fit in
* the on-disk inode root. If the if_broot is currently NULL, then
* if we adding records one will be allocated. The caller must also
* not request that the number of records go below zero, although
* it can go to zero.
*
* ip -- the inode whose if_broot area is changing
* ext_diff -- the change in the number of records, positive or negative,
* requested for the if_broot array.
*/
void
xfs_iroot_realloc(
xfs_inode_t *ip,
int rec_diff,
int whichfork)
{
struct xfs_mount *mp = ip->i_mount;
int cur_max;
xfs_ifork_t *ifp;
struct xfs_btree_block *new_broot;
int new_max;
size_t new_size;
char *np;
char *op;
/*
* Handle the degenerate case quietly.
*/
if (rec_diff == 0) {
return;
}
ifp = XFS_IFORK_PTR(ip, whichfork);
if (rec_diff > 0) {
/*
* If there wasn't any memory allocated before, just
* allocate it now and get out.
*/
if (ifp->if_broot_bytes == 0) {
new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(rec_diff);
ifp->if_broot = kmem_alloc(new_size, KM_SLEEP | KM_NOFS);
ifp->if_broot_bytes = (int)new_size;
return;
}
/*
* If there is already an existing if_broot, then we need
* to realloc() it and shift the pointers to their new
* location. The records don't change location because
* they are kept butted up against the btree block header.
*/
cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
new_max = cur_max + rec_diff;
new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(new_max);
ifp->if_broot = kmem_realloc(ifp->if_broot, new_size,
(size_t)XFS_BMAP_BROOT_SPACE_CALC(cur_max), /* old size */
KM_SLEEP | KM_NOFS);
op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
ifp->if_broot_bytes);
np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
(int)new_size);
ifp->if_broot_bytes = (int)new_size;
ASSERT(ifp->if_broot_bytes <=
XFS_IFORK_SIZE(ip, whichfork) + XFS_BROOT_SIZE_ADJ);
memmove(np, op, cur_max * (uint)sizeof(xfs_dfsbno_t));
return;
}
/*
* rec_diff is less than 0. In this case, we are shrinking the
* if_broot buffer. It must already exist. If we go to zero
* records, just get rid of the root and clear the status bit.
*/
ASSERT((ifp->if_broot != NULL) && (ifp->if_broot_bytes > 0));
cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0);
new_max = cur_max + rec_diff;
ASSERT(new_max >= 0);
if (new_max > 0)
new_size = (size_t)XFS_BMAP_BROOT_SPACE_CALC(new_max);
else
new_size = 0;
if (new_size > 0) {
new_broot = kmem_alloc(new_size, KM_SLEEP | KM_NOFS);
/*
* First copy over the btree block header.
*/
memcpy(new_broot, ifp->if_broot, XFS_BTREE_LBLOCK_LEN);
} else {
new_broot = NULL;
ifp->if_flags &= ~XFS_IFBROOT;
}
/*
* Only copy the records and pointers if there are any.
*/
if (new_max > 0) {
/*
* First copy the records.
*/
op = (char *)XFS_BMBT_REC_ADDR(mp, ifp->if_broot, 1);
np = (char *)XFS_BMBT_REC_ADDR(mp, new_broot, 1);
memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_rec_t));
/*
* Then copy the pointers.
*/
op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1,
ifp->if_broot_bytes);
np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, new_broot, 1,
(int)new_size);
memcpy(np, op, new_max * (uint)sizeof(xfs_dfsbno_t));
}
kmem_free(ifp->if_broot);
ifp->if_broot = new_broot;
ifp->if_broot_bytes = (int)new_size;
ASSERT(ifp->if_broot_bytes <=
XFS_IFORK_SIZE(ip, whichfork) + XFS_BROOT_SIZE_ADJ);
return;
}
/*
* This is called when the amount of space needed for if_data
* is increased or decreased. The change in size is indicated by
* the number of bytes that need to be added or deleted in the
* byte_diff parameter.
*
* If the amount of space needed has decreased below the size of the
* inline buffer, then switch to using the inline buffer. Otherwise,
* use kmem_realloc() or kmem_alloc() to adjust the size of the buffer
* to what is needed.
*
* ip -- the inode whose if_data area is changing
* byte_diff -- the change in the number of bytes, positive or negative,
* requested for the if_data array.
*/
void
xfs_idata_realloc(
xfs_inode_t *ip,
int byte_diff,
int whichfork)
{
xfs_ifork_t *ifp;
int new_size;
int real_size;
if (byte_diff == 0) {
return;
}
ifp = XFS_IFORK_PTR(ip, whichfork);
new_size = (int)ifp->if_bytes + byte_diff;
ASSERT(new_size >= 0);
if (new_size == 0) {
if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
kmem_free(ifp->if_u1.if_data);
}
ifp->if_u1.if_data = NULL;
real_size = 0;
} else if (new_size <= sizeof(ifp->if_u2.if_inline_data)) {
/*
* If the valid extents/data can fit in if_inline_ext/data,
* copy them from the malloc'd vector and free it.
*/
if (ifp->if_u1.if_data == NULL) {
ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
} else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
ASSERT(ifp->if_real_bytes != 0);
memcpy(ifp->if_u2.if_inline_data, ifp->if_u1.if_data,
new_size);
kmem_free(ifp->if_u1.if_data);
ifp->if_u1.if_data = ifp->if_u2.if_inline_data;
}
real_size = 0;
} else {
/*
* Stuck with malloc/realloc.
* For inline data, the underlying buffer must be
* a multiple of 4 bytes in size so that it can be
* logged and stay on word boundaries. We enforce
* that here.
*/
real_size = roundup(new_size, 4);
if (ifp->if_u1.if_data == NULL) {
ASSERT(ifp->if_real_bytes == 0);
ifp->if_u1.if_data = kmem_alloc(real_size,
KM_SLEEP | KM_NOFS);
} else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) {
/*
* Only do the realloc if the underlying size
* is really changing.
*/
if (ifp->if_real_bytes != real_size) {
ifp->if_u1.if_data =
kmem_realloc(ifp->if_u1.if_data,
real_size,
ifp->if_real_bytes,
KM_SLEEP | KM_NOFS);
}
} else {
ASSERT(ifp->if_real_bytes == 0);
ifp->if_u1.if_data = kmem_alloc(real_size,
KM_SLEEP | KM_NOFS);
memcpy(ifp->if_u1.if_data, ifp->if_u2.if_inline_data,
ifp->if_bytes);
}
}
ifp->if_real_bytes = real_size;
ifp->if_bytes = new_size;
ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork));
}
void
xfs_idestroy_fork(
xfs_inode_t *ip,
int whichfork)
{
xfs_ifork_t *ifp;
ifp = XFS_IFORK_PTR(ip, whichfork);
if (ifp->if_broot != NULL) {
kmem_free(ifp->if_broot);
ifp->if_broot = NULL;
}
/*
* If the format is local, then we can't have an extents
* array so just look for an inline data array. If we're
* not local then we may or may not have an extents list,
* so check and free it up if we do.
*/
if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) {
if ((ifp->if_u1.if_data != ifp->if_u2.if_inline_data) &&
(ifp->if_u1.if_data != NULL)) {
ASSERT(ifp->if_real_bytes != 0);
kmem_free(ifp->if_u1.if_data);
ifp->if_u1.if_data = NULL;
ifp->if_real_bytes = 0;
}
} else if ((ifp->if_flags & XFS_IFEXTENTS) &&
((ifp->if_flags & XFS_IFEXTIREC) ||
((ifp->if_u1.if_extents != NULL) &&
(ifp->if_u1.if_extents != ifp->if_u2.if_inline_ext)))) {
ASSERT(ifp->if_real_bytes != 0);
xfs_iext_destroy(ifp);
}
ASSERT(ifp->if_u1.if_extents == NULL ||
ifp->if_u1.if_extents == ifp->if_u2.if_inline_ext);
ASSERT(ifp->if_real_bytes == 0);
if (whichfork == XFS_ATTR_FORK) {
kmem_zone_free(xfs_ifork_zone, ip->i_afp);
ip->i_afp = NULL;
}
}
/*
* This is called to unpin an inode. The caller must have the inode locked
* in at least shared mode so that the buffer cannot be subsequently pinned
* once someone is waiting for it to be unpinned.
*/
static void
xfs_iunpin_nowait(
struct xfs_inode *ip)
{
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
trace_xfs_inode_unpin_nowait(ip, _RET_IP_);
/* Give the log a push to start the unpinning I/O */
xfs_log_force_lsn(ip->i_mount, ip->i_itemp->ili_last_lsn, 0);
}
void
xfs_iunpin_wait(
struct xfs_inode *ip)
{
if (xfs_ipincount(ip)) {
xfs_iunpin_nowait(ip);
wait_event(ip->i_ipin_wait, (xfs_ipincount(ip) == 0));
}
}
/*
* xfs_iextents_copy()
*
* This is called to copy the REAL extents (as opposed to the delayed
* allocation extents) from the inode into the given buffer. It
* returns the number of bytes copied into the buffer.
*
* If there are no delayed allocation extents, then we can just
* memcpy() the extents into the buffer. Otherwise, we need to
* examine each extent in turn and skip those which are delayed.
*/
int
xfs_iextents_copy(
xfs_inode_t *ip,
xfs_bmbt_rec_t *dp,
int whichfork)
{
int copied;
int i;
xfs_ifork_t *ifp;
int nrecs;
xfs_fsblock_t start_block;
ifp = XFS_IFORK_PTR(ip, whichfork);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
ASSERT(ifp->if_bytes > 0);
nrecs = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
XFS_BMAP_TRACE_EXLIST(ip, nrecs, whichfork);
ASSERT(nrecs > 0);
/*
* There are some delayed allocation extents in the
* inode, so copy the extents one at a time and skip
* the delayed ones. There must be at least one
* non-delayed extent.
*/
copied = 0;
for (i = 0; i < nrecs; i++) {
xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
start_block = xfs_bmbt_get_startblock(ep);
if (isnullstartblock(start_block)) {
/*
* It's a delayed allocation extent, so skip it.
*/
continue;
}
/* Translate to on disk format */
put_unaligned(cpu_to_be64(ep->l0), &dp->l0);
put_unaligned(cpu_to_be64(ep->l1), &dp->l1);
dp++;
copied++;
}
ASSERT(copied != 0);
xfs_validate_extents(ifp, copied, XFS_EXTFMT_INODE(ip));
return (copied * (uint)sizeof(xfs_bmbt_rec_t));
}
/*
* Each of the following cases stores data into the same region
* of the on-disk inode, so only one of them can be valid at
* any given time. While it is possible to have conflicting formats
* and log flags, e.g. having XFS_ILOG_?DATA set when the fork is
* in EXTENTS format, this can only happen when the fork has
* changed formats after being modified but before being flushed.
* In these cases, the format always takes precedence, because the
* format indicates the current state of the fork.
*/
/*ARGSUSED*/
STATIC void
xfs_iflush_fork(
xfs_inode_t *ip,
xfs_dinode_t *dip,
xfs_inode_log_item_t *iip,
int whichfork,
xfs_buf_t *bp)
{
char *cp;
xfs_ifork_t *ifp;
xfs_mount_t *mp;
#ifdef XFS_TRANS_DEBUG
int first;
#endif
static const short brootflag[2] =
{ XFS_ILOG_DBROOT, XFS_ILOG_ABROOT };
static const short dataflag[2] =
{ XFS_ILOG_DDATA, XFS_ILOG_ADATA };
static const short extflag[2] =
{ XFS_ILOG_DEXT, XFS_ILOG_AEXT };
if (!iip)
return;
ifp = XFS_IFORK_PTR(ip, whichfork);
/*
* This can happen if we gave up in iformat in an error path,
* for the attribute fork.
*/
if (!ifp) {
ASSERT(whichfork == XFS_ATTR_FORK);
return;
}
cp = XFS_DFORK_PTR(dip, whichfork);
mp = ip->i_mount;
switch (XFS_IFORK_FORMAT(ip, whichfork)) {
case XFS_DINODE_FMT_LOCAL:
if ((iip->ili_format.ilf_fields & dataflag[whichfork]) &&
(ifp->if_bytes > 0)) {
ASSERT(ifp->if_u1.if_data != NULL);
ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork));
memcpy(cp, ifp->if_u1.if_data, ifp->if_bytes);
}
break;
case XFS_DINODE_FMT_EXTENTS:
ASSERT((ifp->if_flags & XFS_IFEXTENTS) ||
!(iip->ili_format.ilf_fields & extflag[whichfork]));
ASSERT((xfs_iext_get_ext(ifp, 0) != NULL) ||
(ifp->if_bytes == 0));
ASSERT((xfs_iext_get_ext(ifp, 0) == NULL) ||
(ifp->if_bytes > 0));
if ((iip->ili_format.ilf_fields & extflag[whichfork]) &&
(ifp->if_bytes > 0)) {
ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) > 0);
(void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp,
whichfork);
}
break;
case XFS_DINODE_FMT_BTREE:
if ((iip->ili_format.ilf_fields & brootflag[whichfork]) &&
(ifp->if_broot_bytes > 0)) {
ASSERT(ifp->if_broot != NULL);
ASSERT(ifp->if_broot_bytes <=
(XFS_IFORK_SIZE(ip, whichfork) +
XFS_BROOT_SIZE_ADJ));
xfs_bmbt_to_bmdr(mp, ifp->if_broot, ifp->if_broot_bytes,
(xfs_bmdr_block_t *)cp,
XFS_DFORK_SIZE(dip, mp, whichfork));
}
break;
case XFS_DINODE_FMT_DEV:
if (iip->ili_format.ilf_fields & XFS_ILOG_DEV) {
ASSERT(whichfork == XFS_DATA_FORK);
xfs_dinode_put_rdev(dip, ip->i_df.if_u2.if_rdev);
}
break;
case XFS_DINODE_FMT_UUID:
if (iip->ili_format.ilf_fields & XFS_ILOG_UUID) {
ASSERT(whichfork == XFS_DATA_FORK);
memcpy(XFS_DFORK_DPTR(dip),
&ip->i_df.if_u2.if_uuid,
sizeof(uuid_t));
}
break;
default:
ASSERT(0);
break;
}
}
STATIC int
xfs_iflush_cluster(
xfs_inode_t *ip,
xfs_buf_t *bp)
{
xfs_mount_t *mp = ip->i_mount;
struct xfs_perag *pag;
unsigned long first_index, mask;
unsigned long inodes_per_cluster;
int ilist_size;
xfs_inode_t **ilist;
xfs_inode_t *iq;
int nr_found;
int clcount = 0;
int bufwasdelwri;
int i;
pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
inodes_per_cluster = XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog;
ilist_size = inodes_per_cluster * sizeof(xfs_inode_t *);
ilist = kmem_alloc(ilist_size, KM_MAYFAIL|KM_NOFS);
if (!ilist)
goto out_put;
mask = ~(((XFS_INODE_CLUSTER_SIZE(mp) >> mp->m_sb.sb_inodelog)) - 1);
first_index = XFS_INO_TO_AGINO(mp, ip->i_ino) & mask;
rcu_read_lock();
/* really need a gang lookup range call here */
nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, (void**)ilist,
first_index, inodes_per_cluster);
if (nr_found == 0)
goto out_free;
for (i = 0; i < nr_found; i++) {
iq = ilist[i];
if (iq == ip)
continue;
/*
* because this is an RCU protected lookup, we could find a
* recently freed or even reallocated inode during the lookup.
* We need to check under the i_flags_lock for a valid inode
* here. Skip it if it is not valid or the wrong inode.
*/
spin_lock(&ip->i_flags_lock);
if (!ip->i_ino ||
(XFS_INO_TO_AGINO(mp, iq->i_ino) & mask) != first_index) {
spin_unlock(&ip->i_flags_lock);
continue;
}
spin_unlock(&ip->i_flags_lock);
/*
* Do an un-protected check to see if the inode is dirty and
* is a candidate for flushing. These checks will be repeated
* later after the appropriate locks are acquired.
*/
if (xfs_inode_clean(iq) && xfs_ipincount(iq) == 0)
continue;
/*
* Try to get locks. If any are unavailable or it is pinned,
* then this inode cannot be flushed and is skipped.
*/
if (!xfs_ilock_nowait(iq, XFS_ILOCK_SHARED))
continue;
if (!xfs_iflock_nowait(iq)) {
xfs_iunlock(iq, XFS_ILOCK_SHARED);
continue;
}
if (xfs_ipincount(iq)) {
xfs_ifunlock(iq);
xfs_iunlock(iq, XFS_ILOCK_SHARED);
continue;
}
/*
* arriving here means that this inode can be flushed. First
* re-check that it's dirty before flushing.
*/
if (!xfs_inode_clean(iq)) {
int error;
error = xfs_iflush_int(iq, bp);
if (error) {
xfs_iunlock(iq, XFS_ILOCK_SHARED);
goto cluster_corrupt_out;
}
clcount++;
} else {
xfs_ifunlock(iq);
}
xfs_iunlock(iq, XFS_ILOCK_SHARED);
}
if (clcount) {
XFS_STATS_INC(xs_icluster_flushcnt);
XFS_STATS_ADD(xs_icluster_flushinode, clcount);
}
out_free:
rcu_read_unlock();
kmem_free(ilist);
out_put:
xfs_perag_put(pag);
return 0;
cluster_corrupt_out:
/*
* Corruption detected in the clustering loop. Invalidate the
* inode buffer and shut down the filesystem.
*/
rcu_read_unlock();
/*
* Clean up the buffer. If it was B_DELWRI, just release it --
* brelse can handle it with no problems. If not, shut down the
* filesystem before releasing the buffer.
*/
bufwasdelwri = XFS_BUF_ISDELAYWRITE(bp);
if (bufwasdelwri)
xfs_buf_relse(bp);
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
if (!bufwasdelwri) {
/*
* Just like incore_relse: if we have b_iodone functions,
* mark the buffer as an error and call them. Otherwise
* mark it as stale and brelse.
*/
if (XFS_BUF_IODONE_FUNC(bp)) {
XFS_BUF_UNDONE(bp);
XFS_BUF_STALE(bp);
XFS_BUF_ERROR(bp,EIO);
xfs_buf_ioend(bp, 0);
} else {
XFS_BUF_STALE(bp);
xfs_buf_relse(bp);
}
}
/*
* Unlocks the flush lock
*/
xfs_iflush_abort(iq);
kmem_free(ilist);
xfs_perag_put(pag);
return XFS_ERROR(EFSCORRUPTED);
}
/*
* xfs_iflush() will write a modified inode's changes out to the
* inode's on disk home. The caller must have the inode lock held
* in at least shared mode and the inode flush completion must be
* active as well. The inode lock will still be held upon return from
* the call and the caller is free to unlock it.
* The inode flush will be completed when the inode reaches the disk.
* The flags indicate how the inode's buffer should be written out.
*/
int
xfs_iflush(
xfs_inode_t *ip,
uint flags)
{
xfs_inode_log_item_t *iip;
xfs_buf_t *bp;
xfs_dinode_t *dip;
xfs_mount_t *mp;
int error;
XFS_STATS_INC(xs_iflush_count);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
ASSERT(!completion_done(&ip->i_flush));
ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
ip->i_d.di_nextents > ip->i_df.if_ext_max);
iip = ip->i_itemp;
mp = ip->i_mount;
/*
* We can't flush the inode until it is unpinned, so wait for it if we
* are allowed to block. We know no one new can pin it, because we are
* holding the inode lock shared and you need to hold it exclusively to
* pin the inode.
*
* If we are not allowed to block, force the log out asynchronously so
* that when we come back the inode will be unpinned. If other inodes
* in the same cluster are dirty, they will probably write the inode
* out for us if they occur after the log force completes.
*/
if (!(flags & SYNC_WAIT) && xfs_ipincount(ip)) {
xfs_iunpin_nowait(ip);
xfs_ifunlock(ip);
return EAGAIN;
}
xfs_iunpin_wait(ip);
/*
* For stale inodes we cannot rely on the backing buffer remaining
* stale in cache for the remaining life of the stale inode and so
* xfs_itobp() below may give us a buffer that no longer contains
* inodes below. We have to check this after ensuring the inode is
* unpinned so that it is safe to reclaim the stale inode after the
* flush call.
*/
if (xfs_iflags_test(ip, XFS_ISTALE)) {
xfs_ifunlock(ip);
return 0;
}
/*
* This may have been unpinned because the filesystem is shutting
* down forcibly. If that's the case we must not write this inode
* to disk, because the log record didn't make it to disk!
*/
if (XFS_FORCED_SHUTDOWN(mp)) {
ip->i_update_core = 0;
if (iip)
iip->ili_format.ilf_fields = 0;
xfs_ifunlock(ip);
return XFS_ERROR(EIO);
}
/*
* Get the buffer containing the on-disk inode.
*/
error = xfs_itobp(mp, NULL, ip, &dip, &bp,
(flags & SYNC_TRYLOCK) ? XBF_TRYLOCK : XBF_LOCK);
if (error || !bp) {
xfs_ifunlock(ip);
return error;
}
/*
* First flush out the inode that xfs_iflush was called with.
*/
error = xfs_iflush_int(ip, bp);
if (error)
goto corrupt_out;
/*
* If the buffer is pinned then push on the log now so we won't
* get stuck waiting in the write for too long.
*/
if (XFS_BUF_ISPINNED(bp))
xfs_log_force(mp, 0);
/*
* inode clustering:
* see if other inodes can be gathered into this write
*/
error = xfs_iflush_cluster(ip, bp);
if (error)
goto cluster_corrupt_out;
if (flags & SYNC_WAIT)
error = xfs_bwrite(mp, bp);
else
xfs_bdwrite(mp, bp);
return error;
corrupt_out:
xfs_buf_relse(bp);
xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
cluster_corrupt_out:
/*
* Unlocks the flush lock
*/
xfs_iflush_abort(ip);
return XFS_ERROR(EFSCORRUPTED);
}
STATIC int
xfs_iflush_int(
xfs_inode_t *ip,
xfs_buf_t *bp)
{
xfs_inode_log_item_t *iip;
xfs_dinode_t *dip;
xfs_mount_t *mp;
#ifdef XFS_TRANS_DEBUG
int first;
#endif
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
ASSERT(!completion_done(&ip->i_flush));
ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
ip->i_d.di_nextents > ip->i_df.if_ext_max);
iip = ip->i_itemp;
mp = ip->i_mount;
/* set *dip = inode's place in the buffer */
dip = (xfs_dinode_t *)xfs_buf_offset(bp, ip->i_imap.im_boffset);
/*
* Clear i_update_core before copying out the data.
* This is for coordination with our timestamp updates
* that don't hold the inode lock. They will always
* update the timestamps BEFORE setting i_update_core,
* so if we clear i_update_core after they set it we
* are guaranteed to see their updates to the timestamps.
* I believe that this depends on strongly ordered memory
* semantics, but we have that. We use the SYNCHRONIZE
* macro to make sure that the compiler does not reorder
* the i_update_core access below the data copy below.
*/
ip->i_update_core = 0;
SYNCHRONIZE();
/*
* Make sure to get the latest timestamps from the Linux inode.
*/
xfs_synchronize_times(ip);
if (XFS_TEST_ERROR(be16_to_cpu(dip->di_magic) != XFS_DINODE_MAGIC,
mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: Bad inode %Lu magic number 0x%x, ptr 0x%p",
__func__, ip->i_ino, be16_to_cpu(dip->di_magic), dip);
goto corrupt_out;
}
if (XFS_TEST_ERROR(ip->i_d.di_magic != XFS_DINODE_MAGIC,
mp, XFS_ERRTAG_IFLUSH_2, XFS_RANDOM_IFLUSH_2)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: Bad inode %Lu, ptr 0x%p, magic number 0x%x",
__func__, ip->i_ino, ip, ip->i_d.di_magic);
goto corrupt_out;
}
if ((ip->i_d.di_mode & S_IFMT) == S_IFREG) {
if (XFS_TEST_ERROR(
(ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
(ip->i_d.di_format != XFS_DINODE_FMT_BTREE),
mp, XFS_ERRTAG_IFLUSH_3, XFS_RANDOM_IFLUSH_3)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: Bad regular inode %Lu, ptr 0x%p",
__func__, ip->i_ino, ip);
goto corrupt_out;
}
} else if ((ip->i_d.di_mode & S_IFMT) == S_IFDIR) {
if (XFS_TEST_ERROR(
(ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS) &&
(ip->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
(ip->i_d.di_format != XFS_DINODE_FMT_LOCAL),
mp, XFS_ERRTAG_IFLUSH_4, XFS_RANDOM_IFLUSH_4)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: Bad directory inode %Lu, ptr 0x%p",
__func__, ip->i_ino, ip);
goto corrupt_out;
}
}
if (XFS_TEST_ERROR(ip->i_d.di_nextents + ip->i_d.di_anextents >
ip->i_d.di_nblocks, mp, XFS_ERRTAG_IFLUSH_5,
XFS_RANDOM_IFLUSH_5)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: detected corrupt incore inode %Lu, "
"total extents = %d, nblocks = %Ld, ptr 0x%p",
__func__, ip->i_ino,
ip->i_d.di_nextents + ip->i_d.di_anextents,
ip->i_d.di_nblocks, ip);
goto corrupt_out;
}
if (XFS_TEST_ERROR(ip->i_d.di_forkoff > mp->m_sb.sb_inodesize,
mp, XFS_ERRTAG_IFLUSH_6, XFS_RANDOM_IFLUSH_6)) {
xfs_alert_tag(mp, XFS_PTAG_IFLUSH,
"%s: bad inode %Lu, forkoff 0x%x, ptr 0x%p",
__func__, ip->i_ino, ip->i_d.di_forkoff, ip);
goto corrupt_out;
}
/*
* bump the flush iteration count, used to detect flushes which
* postdate a log record during recovery.
*/
ip->i_d.di_flushiter++;
/*
* Copy the dirty parts of the inode into the on-disk
* inode. We always copy out the core of the inode,
* because if the inode is dirty at all the core must
* be.
*/
xfs_dinode_to_disk(dip, &ip->i_d);
/* Wrap, we never let the log put out DI_MAX_FLUSH */
if (ip->i_d.di_flushiter == DI_MAX_FLUSH)
ip->i_d.di_flushiter = 0;
/*
* If this is really an old format inode and the superblock version
* has not been updated to support only new format inodes, then
* convert back to the old inode format. If the superblock version
* has been updated, then make the conversion permanent.
*/
ASSERT(ip->i_d.di_version == 1 || xfs_sb_version_hasnlink(&mp->m_sb));
if (ip->i_d.di_version == 1) {
if (!xfs_sb_version_hasnlink(&mp->m_sb)) {
/*
* Convert it back.
*/
ASSERT(ip->i_d.di_nlink <= XFS_MAXLINK_1);
dip->di_onlink = cpu_to_be16(ip->i_d.di_nlink);
} else {
/*
* The superblock version has already been bumped,
* so just make the conversion to the new inode
* format permanent.
*/
ip->i_d.di_version = 2;
dip->di_version = 2;
ip->i_d.di_onlink = 0;
dip->di_onlink = 0;
memset(&(ip->i_d.di_pad[0]), 0, sizeof(ip->i_d.di_pad));
memset(&(dip->di_pad[0]), 0,
sizeof(dip->di_pad));
ASSERT(xfs_get_projid(ip) == 0);
}
}
xfs_iflush_fork(ip, dip, iip, XFS_DATA_FORK, bp);
if (XFS_IFORK_Q(ip))
xfs_iflush_fork(ip, dip, iip, XFS_ATTR_FORK, bp);
xfs_inobp_check(mp, bp);
/*
* We've recorded everything logged in the inode, so we'd
* like to clear the ilf_fields bits so we don't log and
* flush things unnecessarily. However, we can't stop
* logging all this information until the data we've copied
* into the disk buffer is written to disk. If we did we might
* overwrite the copy of the inode in the log with all the
* data after re-logging only part of it, and in the face of
* a crash we wouldn't have all the data we need to recover.
*
* What we do is move the bits to the ili_last_fields field.
* When logging the inode, these bits are moved back to the
* ilf_fields field. In the xfs_iflush_done() routine we
* clear ili_last_fields, since we know that the information
* those bits represent is permanently on disk. As long as
* the flush completes before the inode is logged again, then
* both ilf_fields and ili_last_fields will be cleared.
*
* We can play with the ilf_fields bits here, because the inode
* lock must be held exclusively in order to set bits there
* and the flush lock protects the ili_last_fields bits.
* Set ili_logged so the flush done
* routine can tell whether or not to look in the AIL.
* Also, store the current LSN of the inode so that we can tell
* whether the item has moved in the AIL from xfs_iflush_done().
* In order to read the lsn we need the AIL lock, because
* it is a 64 bit value that cannot be read atomically.
*/
if (iip != NULL && iip->ili_format.ilf_fields != 0) {
iip->ili_last_fields = iip->ili_format.ilf_fields;
iip->ili_format.ilf_fields = 0;
iip->ili_logged = 1;
xfs_trans_ail_copy_lsn(mp->m_ail, &iip->ili_flush_lsn,
&iip->ili_item.li_lsn);
/*
* Attach the function xfs_iflush_done to the inode's
* buffer. This will remove the inode from the AIL
* and unlock the inode's flush lock when the inode is
* completely written to disk.
*/
xfs_buf_attach_iodone(bp, xfs_iflush_done, &iip->ili_item);
ASSERT(XFS_BUF_FSPRIVATE(bp, void *) != NULL);
ASSERT(XFS_BUF_IODONE_FUNC(bp) != NULL);
} else {
/*
* We're flushing an inode which is not in the AIL and has
* not been logged but has i_update_core set. For this
* case we can use a B_DELWRI flush and immediately drop
* the inode flush lock because we can avoid the whole
* AIL state thing. It's OK to drop the flush lock now,
* because we've already locked the buffer and to do anything
* you really need both.
*/
if (iip != NULL) {
ASSERT(iip->ili_logged == 0);
ASSERT(iip->ili_last_fields == 0);
ASSERT((iip->ili_item.li_flags & XFS_LI_IN_AIL) == 0);
}
xfs_ifunlock(ip);
}
return 0;
corrupt_out:
return XFS_ERROR(EFSCORRUPTED);
}
/*
* Return a pointer to the extent record at file index idx.
*/
xfs_bmbt_rec_host_t *
xfs_iext_get_ext(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx) /* index of target extent */
{
ASSERT(idx >= 0);
if ((ifp->if_flags & XFS_IFEXTIREC) && (idx == 0)) {
return ifp->if_u1.if_ext_irec->er_extbuf;
} else if (ifp->if_flags & XFS_IFEXTIREC) {
xfs_ext_irec_t *erp; /* irec pointer */
int erp_idx = 0; /* irec index */
xfs_extnum_t page_idx = idx; /* ext index in target list */
erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 0);
return &erp->er_extbuf[page_idx];
} else if (ifp->if_bytes) {
return &ifp->if_u1.if_extents[idx];
} else {
return NULL;
}
}
/*
* Insert new item(s) into the extent records for incore inode
* fork 'ifp'. 'count' new items are inserted at index 'idx'.
*/
void
xfs_iext_insert(
xfs_inode_t *ip, /* incore inode pointer */
xfs_extnum_t idx, /* starting index of new items */
xfs_extnum_t count, /* number of inserted items */
xfs_bmbt_irec_t *new, /* items to insert */
int state) /* type of extent conversion */
{
xfs_ifork_t *ifp = (state & BMAP_ATTRFORK) ? ip->i_afp : &ip->i_df;
xfs_extnum_t i; /* extent record index */
trace_xfs_iext_insert(ip, idx, new, state, _RET_IP_);
ASSERT(ifp->if_flags & XFS_IFEXTENTS);
xfs_iext_add(ifp, idx, count);
for (i = idx; i < idx + count; i++, new++)
xfs_bmbt_set_all(xfs_iext_get_ext(ifp, i), new);
}
/*
* This is called when the amount of space required for incore file
* extents needs to be increased. The ext_diff parameter stores the
* number of new extents being added and the idx parameter contains
* the extent index where the new extents will be added. If the new
* extents are being appended, then we just need to (re)allocate and
* initialize the space. Otherwise, if the new extents are being
* inserted into the middle of the existing entries, a bit more work
* is required to make room for the new extents to be inserted. The
* caller is responsible for filling in the new extent entries upon
* return.
*/
void
xfs_iext_add(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx, /* index to begin adding exts */
int ext_diff) /* number of extents to add */
{
int byte_diff; /* new bytes being added */
int new_size; /* size of extents after adding */
xfs_extnum_t nextents; /* number of extents in file */
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
ASSERT((idx >= 0) && (idx <= nextents));
byte_diff = ext_diff * sizeof(xfs_bmbt_rec_t);
new_size = ifp->if_bytes + byte_diff;
/*
* If the new number of extents (nextents + ext_diff)
* fits inside the inode, then continue to use the inline
* extent buffer.
*/
if (nextents + ext_diff <= XFS_INLINE_EXTS) {
if (idx < nextents) {
memmove(&ifp->if_u2.if_inline_ext[idx + ext_diff],
&ifp->if_u2.if_inline_ext[idx],
(nextents - idx) * sizeof(xfs_bmbt_rec_t));
memset(&ifp->if_u2.if_inline_ext[idx], 0, byte_diff);
}
ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
ifp->if_real_bytes = 0;
ifp->if_lastex = nextents + ext_diff;
}
/*
* Otherwise use a linear (direct) extent list.
* If the extents are currently inside the inode,
* xfs_iext_realloc_direct will switch us from
* inline to direct extent allocation mode.
*/
else if (nextents + ext_diff <= XFS_LINEAR_EXTS) {
xfs_iext_realloc_direct(ifp, new_size);
if (idx < nextents) {
memmove(&ifp->if_u1.if_extents[idx + ext_diff],
&ifp->if_u1.if_extents[idx],
(nextents - idx) * sizeof(xfs_bmbt_rec_t));
memset(&ifp->if_u1.if_extents[idx], 0, byte_diff);
}
}
/* Indirection array */
else {
xfs_ext_irec_t *erp;
int erp_idx = 0;
int page_idx = idx;
ASSERT(nextents + ext_diff > XFS_LINEAR_EXTS);
if (ifp->if_flags & XFS_IFEXTIREC) {
erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 1);
} else {
xfs_iext_irec_init(ifp);
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
erp = ifp->if_u1.if_ext_irec;
}
/* Extents fit in target extent page */
if (erp && erp->er_extcount + ext_diff <= XFS_LINEAR_EXTS) {
if (page_idx < erp->er_extcount) {
memmove(&erp->er_extbuf[page_idx + ext_diff],
&erp->er_extbuf[page_idx],
(erp->er_extcount - page_idx) *
sizeof(xfs_bmbt_rec_t));
memset(&erp->er_extbuf[page_idx], 0, byte_diff);
}
erp->er_extcount += ext_diff;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff);
}
/* Insert a new extent page */
else if (erp) {
xfs_iext_add_indirect_multi(ifp,
erp_idx, page_idx, ext_diff);
}
/*
* If extent(s) are being appended to the last page in
* the indirection array and the new extent(s) don't fit
* in the page, then erp is NULL and erp_idx is set to
* the next index needed in the indirection array.
*/
else {
int count = ext_diff;
while (count) {
erp = xfs_iext_irec_new(ifp, erp_idx);
erp->er_extcount = count;
count -= MIN(count, (int)XFS_LINEAR_EXTS);
if (count) {
erp_idx++;
}
}
}
}
ifp->if_bytes = new_size;
}
/*
* This is called when incore extents are being added to the indirection
* array and the new extents do not fit in the target extent list. The
* erp_idx parameter contains the irec index for the target extent list
* in the indirection array, and the idx parameter contains the extent
* index within the list. The number of extents being added is stored
* in the count parameter.
*
* |-------| |-------|
* | | | | idx - number of extents before idx
* | idx | | count |
* | | | | count - number of extents being inserted at idx
* |-------| |-------|
* | count | | nex2 | nex2 - number of extents after idx + count
* |-------| |-------|
*/
void
xfs_iext_add_indirect_multi(
xfs_ifork_t *ifp, /* inode fork pointer */
int erp_idx, /* target extent irec index */
xfs_extnum_t idx, /* index within target list */
int count) /* new extents being added */
{
int byte_diff; /* new bytes being added */
xfs_ext_irec_t *erp; /* pointer to irec entry */
xfs_extnum_t ext_diff; /* number of extents to add */
xfs_extnum_t ext_cnt; /* new extents still needed */
xfs_extnum_t nex2; /* extents after idx + count */
xfs_bmbt_rec_t *nex2_ep = NULL; /* temp list for nex2 extents */
int nlists; /* number of irec's (lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
erp = &ifp->if_u1.if_ext_irec[erp_idx];
nex2 = erp->er_extcount - idx;
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
/*
* Save second part of target extent list
* (all extents past */
if (nex2) {
byte_diff = nex2 * sizeof(xfs_bmbt_rec_t);
nex2_ep = (xfs_bmbt_rec_t *) kmem_alloc(byte_diff, KM_NOFS);
memmove(nex2_ep, &erp->er_extbuf[idx], byte_diff);
erp->er_extcount -= nex2;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, -nex2);
memset(&erp->er_extbuf[idx], 0, byte_diff);
}
/*
* Add the new extents to the end of the target
* list, then allocate new irec record(s) and
* extent buffer(s) as needed to store the rest
* of the new extents.
*/
ext_cnt = count;
ext_diff = MIN(ext_cnt, (int)XFS_LINEAR_EXTS - erp->er_extcount);
if (ext_diff) {
erp->er_extcount += ext_diff;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff);
ext_cnt -= ext_diff;
}
while (ext_cnt) {
erp_idx++;
erp = xfs_iext_irec_new(ifp, erp_idx);
ext_diff = MIN(ext_cnt, (int)XFS_LINEAR_EXTS);
erp->er_extcount = ext_diff;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff);
ext_cnt -= ext_diff;
}
/* Add nex2 extents back to indirection array */
if (nex2) {
xfs_extnum_t ext_avail;
int i;
byte_diff = nex2 * sizeof(xfs_bmbt_rec_t);
ext_avail = XFS_LINEAR_EXTS - erp->er_extcount;
i = 0;
/*
* If nex2 extents fit in the current page, append
* nex2_ep after the new extents.
*/
if (nex2 <= ext_avail) {
i = erp->er_extcount;
}
/*
* Otherwise, check if space is available in the
* next page.
*/
else if ((erp_idx < nlists - 1) &&
(nex2 <= (ext_avail = XFS_LINEAR_EXTS -
ifp->if_u1.if_ext_irec[erp_idx+1].er_extcount))) {
erp_idx++;
erp++;
/* Create a hole for nex2 extents */
memmove(&erp->er_extbuf[nex2], erp->er_extbuf,
erp->er_extcount * sizeof(xfs_bmbt_rec_t));
}
/*
* Final choice, create a new extent page for
* nex2 extents.
*/
else {
erp_idx++;
erp = xfs_iext_irec_new(ifp, erp_idx);
}
memmove(&erp->er_extbuf[i], nex2_ep, byte_diff);
kmem_free(nex2_ep);
erp->er_extcount += nex2;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, nex2);
}
}
/*
* This is called when the amount of space required for incore file
* extents needs to be decreased. The ext_diff parameter stores the
* number of extents to be removed and the idx parameter contains
* the extent index where the extents will be removed from.
*
* If the amount of space needed has decreased below the linear
* limit, XFS_IEXT_BUFSZ, then switch to using the contiguous
* extent array. Otherwise, use kmem_realloc() to adjust the
* size to what is needed.
*/
void
xfs_iext_remove(
xfs_inode_t *ip, /* incore inode pointer */
xfs_extnum_t idx, /* index to begin removing exts */
int ext_diff, /* number of extents to remove */
int state) /* type of extent conversion */
{
xfs_ifork_t *ifp = (state & BMAP_ATTRFORK) ? ip->i_afp : &ip->i_df;
xfs_extnum_t nextents; /* number of extents in file */
int new_size; /* size of extents after removal */
trace_xfs_iext_remove(ip, idx, state, _RET_IP_);
ASSERT(ext_diff > 0);
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
new_size = (nextents - ext_diff) * sizeof(xfs_bmbt_rec_t);
if (new_size == 0) {
xfs_iext_destroy(ifp);
} else if (ifp->if_flags & XFS_IFEXTIREC) {
xfs_iext_remove_indirect(ifp, idx, ext_diff);
} else if (ifp->if_real_bytes) {
xfs_iext_remove_direct(ifp, idx, ext_diff);
} else {
xfs_iext_remove_inline(ifp, idx, ext_diff);
}
ifp->if_bytes = new_size;
}
/*
* This removes ext_diff extents from the inline buffer, beginning
* at extent index idx.
*/
void
xfs_iext_remove_inline(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx, /* index to begin removing exts */
int ext_diff) /* number of extents to remove */
{
int nextents; /* number of extents in file */
ASSERT(!(ifp->if_flags & XFS_IFEXTIREC));
ASSERT(idx < XFS_INLINE_EXTS);
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
ASSERT(((nextents - ext_diff) > 0) &&
(nextents - ext_diff) < XFS_INLINE_EXTS);
if (idx + ext_diff < nextents) {
memmove(&ifp->if_u2.if_inline_ext[idx],
&ifp->if_u2.if_inline_ext[idx + ext_diff],
(nextents - (idx + ext_diff)) *
sizeof(xfs_bmbt_rec_t));
memset(&ifp->if_u2.if_inline_ext[nextents - ext_diff],
0, ext_diff * sizeof(xfs_bmbt_rec_t));
} else {
memset(&ifp->if_u2.if_inline_ext[idx], 0,
ext_diff * sizeof(xfs_bmbt_rec_t));
}
}
/*
* This removes ext_diff extents from a linear (direct) extent list,
* beginning at extent index idx. If the extents are being removed
* from the end of the list (ie. truncate) then we just need to re-
* allocate the list to remove the extra space. Otherwise, if the
* extents are being removed from the middle of the existing extent
* entries, then we first need to move the extent records beginning
* at idx + ext_diff up in the list to overwrite the records being
* removed, then remove the extra space via kmem_realloc.
*/
void
xfs_iext_remove_direct(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx, /* index to begin removing exts */
int ext_diff) /* number of extents to remove */
{
xfs_extnum_t nextents; /* number of extents in file */
int new_size; /* size of extents after removal */
ASSERT(!(ifp->if_flags & XFS_IFEXTIREC));
new_size = ifp->if_bytes -
(ext_diff * sizeof(xfs_bmbt_rec_t));
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
if (new_size == 0) {
xfs_iext_destroy(ifp);
return;
}
/* Move extents up in the list (if needed) */
if (idx + ext_diff < nextents) {
memmove(&ifp->if_u1.if_extents[idx],
&ifp->if_u1.if_extents[idx + ext_diff],
(nextents - (idx + ext_diff)) *
sizeof(xfs_bmbt_rec_t));
}
memset(&ifp->if_u1.if_extents[nextents - ext_diff],
0, ext_diff * sizeof(xfs_bmbt_rec_t));
/*
* Reallocate the direct extent list. If the extents
* will fit inside the inode then xfs_iext_realloc_direct
* will switch from direct to inline extent allocation
* mode for us.
*/
xfs_iext_realloc_direct(ifp, new_size);
ifp->if_bytes = new_size;
}
/*
* This is called when incore extents are being removed from the
* indirection array and the extents being removed span multiple extent
* buffers. The idx parameter contains the file extent index where we
* want to begin removing extents, and the count parameter contains
* how many extents need to be removed.
*
* |-------| |-------|
* | nex1 | | | nex1 - number of extents before idx
* |-------| | count |
* | | | | count - number of extents being removed at idx
* | count | |-------|
* | | | nex2 | nex2 - number of extents after idx + count
* |-------| |-------|
*/
void
xfs_iext_remove_indirect(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t idx, /* index to begin removing extents */
int count) /* number of extents to remove */
{
xfs_ext_irec_t *erp; /* indirection array pointer */
int erp_idx = 0; /* indirection array index */
xfs_extnum_t ext_cnt; /* extents left to remove */
xfs_extnum_t ext_diff; /* extents to remove in current list */
xfs_extnum_t nex1; /* number of extents before idx */
xfs_extnum_t nex2; /* extents after idx + count */
int page_idx = idx; /* index in target extent list */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 0);
ASSERT(erp != NULL);
nex1 = page_idx;
ext_cnt = count;
while (ext_cnt) {
nex2 = MAX((erp->er_extcount - (nex1 + ext_cnt)), 0);
ext_diff = MIN(ext_cnt, (erp->er_extcount - nex1));
/*
* Check for deletion of entire list;
* xfs_iext_irec_remove() updates extent offsets.
*/
if (ext_diff == erp->er_extcount) {
xfs_iext_irec_remove(ifp, erp_idx);
ext_cnt -= ext_diff;
nex1 = 0;
if (ext_cnt) {
ASSERT(erp_idx < ifp->if_real_bytes /
XFS_IEXT_BUFSZ);
erp = &ifp->if_u1.if_ext_irec[erp_idx];
nex1 = 0;
continue;
} else {
break;
}
}
/* Move extents up (if needed) */
if (nex2) {
memmove(&erp->er_extbuf[nex1],
&erp->er_extbuf[nex1 + ext_diff],
nex2 * sizeof(xfs_bmbt_rec_t));
}
/* Zero out rest of page */
memset(&erp->er_extbuf[nex1 + nex2], 0, (XFS_IEXT_BUFSZ -
((nex1 + nex2) * sizeof(xfs_bmbt_rec_t))));
/* Update remaining counters */
erp->er_extcount -= ext_diff;
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, -ext_diff);
ext_cnt -= ext_diff;
nex1 = 0;
erp_idx++;
erp++;
}
ifp->if_bytes -= count * sizeof(xfs_bmbt_rec_t);
xfs_iext_irec_compact(ifp);
}
/*
* Create, destroy, or resize a linear (direct) block of extents.
*/
void
xfs_iext_realloc_direct(
xfs_ifork_t *ifp, /* inode fork pointer */
int new_size) /* new size of extents */
{
int rnew_size; /* real new size of extents */
rnew_size = new_size;
ASSERT(!(ifp->if_flags & XFS_IFEXTIREC) ||
((new_size >= 0) && (new_size <= XFS_IEXT_BUFSZ) &&
(new_size != ifp->if_real_bytes)));
/* Free extent records */
if (new_size == 0) {
xfs_iext_destroy(ifp);
}
/* Resize direct extent list and zero any new bytes */
else if (ifp->if_real_bytes) {
/* Check if extents will fit inside the inode */
if (new_size <= XFS_INLINE_EXTS * sizeof(xfs_bmbt_rec_t)) {
xfs_iext_direct_to_inline(ifp, new_size /
(uint)sizeof(xfs_bmbt_rec_t));
ifp->if_bytes = new_size;
return;
}
if (!is_power_of_2(new_size)){
rnew_size = roundup_pow_of_two(new_size);
}
if (rnew_size != ifp->if_real_bytes) {
ifp->if_u1.if_extents =
kmem_realloc(ifp->if_u1.if_extents,
rnew_size,
ifp->if_real_bytes, KM_NOFS);
}
if (rnew_size > ifp->if_real_bytes) {
memset(&ifp->if_u1.if_extents[ifp->if_bytes /
(uint)sizeof(xfs_bmbt_rec_t)], 0,
rnew_size - ifp->if_real_bytes);
}
}
/*
* Switch from the inline extent buffer to a direct
* extent list. Be sure to include the inline extent
* bytes in new_size.
*/
else {
new_size += ifp->if_bytes;
if (!is_power_of_2(new_size)) {
rnew_size = roundup_pow_of_two(new_size);
}
xfs_iext_inline_to_direct(ifp, rnew_size);
}
ifp->if_real_bytes = rnew_size;
ifp->if_bytes = new_size;
}
/*
* Switch from linear (direct) extent records to inline buffer.
*/
void
xfs_iext_direct_to_inline(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t nextents) /* number of extents in file */
{
ASSERT(ifp->if_flags & XFS_IFEXTENTS);
ASSERT(nextents <= XFS_INLINE_EXTS);
/*
* The inline buffer was zeroed when we switched
* from inline to direct extent allocation mode,
* so we don't need to clear it here.
*/
memcpy(ifp->if_u2.if_inline_ext, ifp->if_u1.if_extents,
nextents * sizeof(xfs_bmbt_rec_t));
kmem_free(ifp->if_u1.if_extents);
ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
ifp->if_real_bytes = 0;
}
/*
* Switch from inline buffer to linear (direct) extent records.
* new_size should already be rounded up to the next power of 2
* by the caller (when appropriate), so use new_size as it is.
* However, since new_size may be rounded up, we can't update
* if_bytes here. It is the caller's responsibility to update
* if_bytes upon return.
*/
void
xfs_iext_inline_to_direct(
xfs_ifork_t *ifp, /* inode fork pointer */
int new_size) /* number of extents in file */
{
ifp->if_u1.if_extents = kmem_alloc(new_size, KM_NOFS);
memset(ifp->if_u1.if_extents, 0, new_size);
if (ifp->if_bytes) {
memcpy(ifp->if_u1.if_extents, ifp->if_u2.if_inline_ext,
ifp->if_bytes);
memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS *
sizeof(xfs_bmbt_rec_t));
}
ifp->if_real_bytes = new_size;
}
/*
* Resize an extent indirection array to new_size bytes.
*/
STATIC void
xfs_iext_realloc_indirect(
xfs_ifork_t *ifp, /* inode fork pointer */
int new_size) /* new indirection array size */
{
int nlists; /* number of irec's (ex lists) */
int size; /* current indirection array size */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
size = nlists * sizeof(xfs_ext_irec_t);
ASSERT(ifp->if_real_bytes);
ASSERT((new_size >= 0) && (new_size != size));
if (new_size == 0) {
xfs_iext_destroy(ifp);
} else {
ifp->if_u1.if_ext_irec = (xfs_ext_irec_t *)
kmem_realloc(ifp->if_u1.if_ext_irec,
new_size, size, KM_NOFS);
}
}
/*
* Switch from indirection array to linear (direct) extent allocations.
*/
STATIC void
xfs_iext_indirect_to_direct(
xfs_ifork_t *ifp) /* inode fork pointer */
{
xfs_bmbt_rec_host_t *ep; /* extent record pointer */
xfs_extnum_t nextents; /* number of extents in file */
int size; /* size of file extents */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
ASSERT(nextents <= XFS_LINEAR_EXTS);
size = nextents * sizeof(xfs_bmbt_rec_t);
xfs_iext_irec_compact_pages(ifp);
ASSERT(ifp->if_real_bytes == XFS_IEXT_BUFSZ);
ep = ifp->if_u1.if_ext_irec->er_extbuf;
kmem_free(ifp->if_u1.if_ext_irec);
ifp->if_flags &= ~XFS_IFEXTIREC;
ifp->if_u1.if_extents = ep;
ifp->if_bytes = size;
if (nextents < XFS_LINEAR_EXTS) {
xfs_iext_realloc_direct(ifp, size);
}
}
/*
* Free incore file extents.
*/
void
xfs_iext_destroy(
xfs_ifork_t *ifp) /* inode fork pointer */
{
if (ifp->if_flags & XFS_IFEXTIREC) {
int erp_idx;
int nlists;
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
for (erp_idx = nlists - 1; erp_idx >= 0 ; erp_idx--) {
xfs_iext_irec_remove(ifp, erp_idx);
}
ifp->if_flags &= ~XFS_IFEXTIREC;
} else if (ifp->if_real_bytes) {
kmem_free(ifp->if_u1.if_extents);
} else if (ifp->if_bytes) {
memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS *
sizeof(xfs_bmbt_rec_t));
}
ifp->if_u1.if_extents = NULL;
ifp->if_real_bytes = 0;
ifp->if_bytes = 0;
}
/*
* Return a pointer to the extent record for file system block bno.
*/
xfs_bmbt_rec_host_t * /* pointer to found extent record */
xfs_iext_bno_to_ext(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_fileoff_t bno, /* block number to search for */
xfs_extnum_t *idxp) /* index of target extent */
{
xfs_bmbt_rec_host_t *base; /* pointer to first extent */
xfs_filblks_t blockcount = 0; /* number of blocks in extent */
xfs_bmbt_rec_host_t *ep = NULL; /* pointer to target extent */
xfs_ext_irec_t *erp = NULL; /* indirection array pointer */
int high; /* upper boundary in search */
xfs_extnum_t idx = 0; /* index of target extent */
int low; /* lower boundary in search */
xfs_extnum_t nextents; /* number of file extents */
xfs_fileoff_t startoff = 0; /* start offset of extent */
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
if (nextents == 0) {
*idxp = 0;
return NULL;
}
low = 0;
if (ifp->if_flags & XFS_IFEXTIREC) {
/* Find target extent list */
int erp_idx = 0;
erp = xfs_iext_bno_to_irec(ifp, bno, &erp_idx);
base = erp->er_extbuf;
high = erp->er_extcount - 1;
} else {
base = ifp->if_u1.if_extents;
high = nextents - 1;
}
/* Binary search extent records */
while (low <= high) {
idx = (low + high) >> 1;
ep = base + idx;
startoff = xfs_bmbt_get_startoff(ep);
blockcount = xfs_bmbt_get_blockcount(ep);
if (bno < startoff) {
high = idx - 1;
} else if (bno >= startoff + blockcount) {
low = idx + 1;
} else {
/* Convert back to file-based extent index */
if (ifp->if_flags & XFS_IFEXTIREC) {
idx += erp->er_extoff;
}
*idxp = idx;
return ep;
}
}
/* Convert back to file-based extent index */
if (ifp->if_flags & XFS_IFEXTIREC) {
idx += erp->er_extoff;
}
if (bno >= startoff + blockcount) {
if (++idx == nextents) {
ep = NULL;
} else {
ep = xfs_iext_get_ext(ifp, idx);
}
}
*idxp = idx;
return ep;
}
/*
* Return a pointer to the indirection array entry containing the
* extent record for filesystem block bno. Store the index of the
* target irec in *erp_idxp.
*/
xfs_ext_irec_t * /* pointer to found extent record */
xfs_iext_bno_to_irec(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_fileoff_t bno, /* block number to search for */
int *erp_idxp) /* irec index of target ext list */
{
xfs_ext_irec_t *erp = NULL; /* indirection array pointer */
xfs_ext_irec_t *erp_next; /* next indirection array entry */
int erp_idx; /* indirection array index */
int nlists; /* number of extent irec's (lists) */
int high; /* binary search upper limit */
int low; /* binary search lower limit */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
erp_idx = 0;
low = 0;
high = nlists - 1;
while (low <= high) {
erp_idx = (low + high) >> 1;
erp = &ifp->if_u1.if_ext_irec[erp_idx];
erp_next = erp_idx < nlists - 1 ? erp + 1 : NULL;
if (bno < xfs_bmbt_get_startoff(erp->er_extbuf)) {
high = erp_idx - 1;
} else if (erp_next && bno >=
xfs_bmbt_get_startoff(erp_next->er_extbuf)) {
low = erp_idx + 1;
} else {
break;
}
}
*erp_idxp = erp_idx;
return erp;
}
/*
* Return a pointer to the indirection array entry containing the
* extent record at file extent index *idxp. Store the index of the
* target irec in *erp_idxp and store the page index of the target
* extent record in *idxp.
*/
xfs_ext_irec_t *
xfs_iext_idx_to_irec(
xfs_ifork_t *ifp, /* inode fork pointer */
xfs_extnum_t *idxp, /* extent index (file -> page) */
int *erp_idxp, /* pointer to target irec */
int realloc) /* new bytes were just added */
{
xfs_ext_irec_t *prev; /* pointer to previous irec */
xfs_ext_irec_t *erp = NULL; /* pointer to current irec */
int erp_idx; /* indirection array index */
int nlists; /* number of irec's (ex lists) */
int high; /* binary search upper limit */
int low; /* binary search lower limit */
xfs_extnum_t page_idx = *idxp; /* extent index in target list */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
ASSERT(page_idx >= 0 && page_idx <=
ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t));
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
erp_idx = 0;
low = 0;
high = nlists - 1;
/* Binary search extent irec's */
while (low <= high) {
erp_idx = (low + high) >> 1;
erp = &ifp->if_u1.if_ext_irec[erp_idx];
prev = erp_idx > 0 ? erp - 1 : NULL;
if (page_idx < erp->er_extoff || (page_idx == erp->er_extoff &&
realloc && prev && prev->er_extcount < XFS_LINEAR_EXTS)) {
high = erp_idx - 1;
} else if (page_idx > erp->er_extoff + erp->er_extcount ||
(page_idx == erp->er_extoff + erp->er_extcount &&
!realloc)) {
low = erp_idx + 1;
} else if (page_idx == erp->er_extoff + erp->er_extcount &&
erp->er_extcount == XFS_LINEAR_EXTS) {
ASSERT(realloc);
page_idx = 0;
erp_idx++;
erp = erp_idx < nlists ? erp + 1 : NULL;
break;
} else {
page_idx -= erp->er_extoff;
break;
}
}
*idxp = page_idx;
*erp_idxp = erp_idx;
return(erp);
}
/*
* Allocate and initialize an indirection array once the space needed
* for incore extents increases above XFS_IEXT_BUFSZ.
*/
void
xfs_iext_irec_init(
xfs_ifork_t *ifp) /* inode fork pointer */
{
xfs_ext_irec_t *erp; /* indirection array pointer */
xfs_extnum_t nextents; /* number of extents in file */
ASSERT(!(ifp->if_flags & XFS_IFEXTIREC));
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
ASSERT(nextents <= XFS_LINEAR_EXTS);
erp = kmem_alloc(sizeof(xfs_ext_irec_t), KM_NOFS);
if (nextents == 0) {
ifp->if_u1.if_extents = kmem_alloc(XFS_IEXT_BUFSZ, KM_NOFS);
} else if (!ifp->if_real_bytes) {
xfs_iext_inline_to_direct(ifp, XFS_IEXT_BUFSZ);
} else if (ifp->if_real_bytes < XFS_IEXT_BUFSZ) {
xfs_iext_realloc_direct(ifp, XFS_IEXT_BUFSZ);
}
erp->er_extbuf = ifp->if_u1.if_extents;
erp->er_extcount = nextents;
erp->er_extoff = 0;
ifp->if_flags |= XFS_IFEXTIREC;
ifp->if_real_bytes = XFS_IEXT_BUFSZ;
ifp->if_bytes = nextents * sizeof(xfs_bmbt_rec_t);
ifp->if_u1.if_ext_irec = erp;
return;
}
/*
* Allocate and initialize a new entry in the indirection array.
*/
xfs_ext_irec_t *
xfs_iext_irec_new(
xfs_ifork_t *ifp, /* inode fork pointer */
int erp_idx) /* index for new irec */
{
xfs_ext_irec_t *erp; /* indirection array pointer */
int i; /* loop counter */
int nlists; /* number of irec's (ex lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
/* Resize indirection array */
xfs_iext_realloc_indirect(ifp, ++nlists *
sizeof(xfs_ext_irec_t));
/*
* Move records down in the array so the
* new page can use erp_idx.
*/
erp = ifp->if_u1.if_ext_irec;
for (i = nlists - 1; i > erp_idx; i--) {
memmove(&erp[i], &erp[i-1], sizeof(xfs_ext_irec_t));
}
ASSERT(i == erp_idx);
/* Initialize new extent record */
erp = ifp->if_u1.if_ext_irec;
erp[erp_idx].er_extbuf = kmem_alloc(XFS_IEXT_BUFSZ, KM_NOFS);
ifp->if_real_bytes = nlists * XFS_IEXT_BUFSZ;
memset(erp[erp_idx].er_extbuf, 0, XFS_IEXT_BUFSZ);
erp[erp_idx].er_extcount = 0;
erp[erp_idx].er_extoff = erp_idx > 0 ?
erp[erp_idx-1].er_extoff + erp[erp_idx-1].er_extcount : 0;
return (&erp[erp_idx]);
}
/*
* Remove a record from the indirection array.
*/
void
xfs_iext_irec_remove(
xfs_ifork_t *ifp, /* inode fork pointer */
int erp_idx) /* irec index to remove */
{
xfs_ext_irec_t *erp; /* indirection array pointer */
int i; /* loop counter */
int nlists; /* number of irec's (ex lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
erp = &ifp->if_u1.if_ext_irec[erp_idx];
if (erp->er_extbuf) {
xfs_iext_irec_update_extoffs(ifp, erp_idx + 1,
-erp->er_extcount);
kmem_free(erp->er_extbuf);
}
/* Compact extent records */
erp = ifp->if_u1.if_ext_irec;
for (i = erp_idx; i < nlists - 1; i++) {
memmove(&erp[i], &erp[i+1], sizeof(xfs_ext_irec_t));
}
/*
* Manually free the last extent record from the indirection
* array. A call to xfs_iext_realloc_indirect() with a size
* of zero would result in a call to xfs_iext_destroy() which
* would in turn call this function again, creating a nasty
* infinite loop.
*/
if (--nlists) {
xfs_iext_realloc_indirect(ifp,
nlists * sizeof(xfs_ext_irec_t));
} else {
kmem_free(ifp->if_u1.if_ext_irec);
}
ifp->if_real_bytes = nlists * XFS_IEXT_BUFSZ;
}
/*
* This is called to clean up large amounts of unused memory allocated
* by the indirection array. Before compacting anything though, verify
* that the indirection array is still needed and switch back to the
* linear extent list (or even the inline buffer) if possible. The
* compaction policy is as follows:
*
* Full Compaction: Extents fit into a single page (or inline buffer)
* Partial Compaction: Extents occupy less than 50% of allocated space
* No Compaction: Extents occupy at least 50% of allocated space
*/
void
xfs_iext_irec_compact(
xfs_ifork_t *ifp) /* inode fork pointer */
{
xfs_extnum_t nextents; /* number of extents in file */
int nlists; /* number of irec's (ex lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
if (nextents == 0) {
xfs_iext_destroy(ifp);
} else if (nextents <= XFS_INLINE_EXTS) {
xfs_iext_indirect_to_direct(ifp);
xfs_iext_direct_to_inline(ifp, nextents);
} else if (nextents <= XFS_LINEAR_EXTS) {
xfs_iext_indirect_to_direct(ifp);
} else if (nextents < (nlists * XFS_LINEAR_EXTS) >> 1) {
xfs_iext_irec_compact_pages(ifp);
}
}
/*
* Combine extents from neighboring extent pages.
*/
void
xfs_iext_irec_compact_pages(
xfs_ifork_t *ifp) /* inode fork pointer */
{
xfs_ext_irec_t *erp, *erp_next;/* pointers to irec entries */
int erp_idx = 0; /* indirection array index */
int nlists; /* number of irec's (ex lists) */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
while (erp_idx < nlists - 1) {
erp = &ifp->if_u1.if_ext_irec[erp_idx];
erp_next = erp + 1;
if (erp_next->er_extcount <=
(XFS_LINEAR_EXTS - erp->er_extcount)) {
memcpy(&erp->er_extbuf[erp->er_extcount],
erp_next->er_extbuf, erp_next->er_extcount *
sizeof(xfs_bmbt_rec_t));
erp->er_extcount += erp_next->er_extcount;
/*
* Free page before removing extent record
* so er_extoffs don't get modified in
* xfs_iext_irec_remove.
*/
kmem_free(erp_next->er_extbuf);
erp_next->er_extbuf = NULL;
xfs_iext_irec_remove(ifp, erp_idx + 1);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
} else {
erp_idx++;
}
}
}
/*
* This is called to update the er_extoff field in the indirection
* array when extents have been added or removed from one of the
* extent lists. erp_idx contains the irec index to begin updating
* at and ext_diff contains the number of extents that were added
* or removed.
*/
void
xfs_iext_irec_update_extoffs(
xfs_ifork_t *ifp, /* inode fork pointer */
int erp_idx, /* irec index to update */
int ext_diff) /* number of new extents */
{
int i; /* loop counter */
int nlists; /* number of irec's (ex lists */
ASSERT(ifp->if_flags & XFS_IFEXTIREC);
nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
for (i = erp_idx; i < nlists; i++) {
ifp->if_u1.if_ext_irec[i].er_extoff += ext_diff;
}
}
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